A
bill
to
Give effect to, and make provision in connection with, an agreement between the governments of the United Kingdom and the Republic of Mauritius concerning the Chagos Archipelago.
B e it enacted by the King’s most Excellent Majesty, by and with the advice and consent of the Lords Spiritual and Temporal, and Commons, in this present Parliament assembled, and by the authority of the same, as follows:—
In this Act, “the Treaty” means the agreement entitled “Agreement between
the Government of the United Kingdom of Great Britain and Northern Ireland
and the Government of the Republic of Mauritius concerning the Chagos
Archipelago including Diego Garcia” that was signed at London and Port
Louis on 22 May 2025.
Sections
3
to
5
of this Act come into force only when the Secretary of State
has sought to negotiate an amendment to Article 11 of the Treaty to ensure
that the United Kingdom would cease to make payments to the government
of Mauritius in the event that the use of the Base for military purposes became
impossible.
The time at which that happens is referred to in this Act as “commencement”.
The Secretary of State must publish in the London Gazette notice of that time.
Within six months of the day on which this Act is passed, the Secretary of
State must conduct a referendum of the Chagossian community.
The referendum must be conducted in writing and in a format and language
as considered appropriate by the Secretary of State to be satisfied the response
will be valid.
The question to be put to the Chagossian community in the referendum is
stated in subsection
(5)
.
“In recognising the international principles of self-determination, do you agree that the implementation of the Treaty agreed between the United Kingdom and Mauritius must guarantee the rights of Chagossians in a legal right—
(a)
of resettlement on the Islands of the Chagos Archipelago other than
Diego Garcia,(b)
of participation in the operation in and opportunities of working in
and visiting Diego Garcia, and(c)
to be involved in decision making on the operation of the Trust Fund
for the benefit of the Chagossian Community?”
Within 30 days of the result of the referendum the Secretary of State must
lay a statement before both Houses of Parliament setting out how they intend
to respond to the referendum.
In this section, “Chagossian community” means those Chagossians identified
by the Secretary of State who will be impacted by the Act.
His Majesty is no longer sovereign over the area comprising the British Indian
Ocean Territory immediately before commencement, and no longer has
jurisdiction over that area except in relation to Diego Garcia (see section
4
).
Accordingly—
the British Indian Ocean Territory (Constitution) Order 2004 is revoked,
and
in Schedule 6 to the British Nationality Act 1981 (list of British overseas
territories for the purposes of that Act and the Interpretation Act 1978),
the entry for the British Indian Ocean Territory is repealed.
The law of the British Indian Ocean Territory immediately before
commencement continues as the law of Diego Garcia.
Any legislation or rule of law of any of His Majesty’s dominions that related
to the British Indian Ocean Territory immediately before commencement
relates in the same way to Diego Garcia.
It follows, in particular, that His Majesty has under his prerogative the like
powers to make laws for Diego Garcia as His Majesty had before
commencement for the British Indian Ocean Territory.
are subject to any other change in the law taking effect at or after
commencement (and do not limit any power to make such changes).
In this Act, “Diego Garcia” includes the whole area over which the United
Kingdom is entitled to exercise jurisdiction by virtue of Articles 2 and 9 of
the Treaty.
In this section , “the 1981 Act” means the British Nationality Act 1981 .
Section
4
(2)
does not apply to
the 1981 Act
or any instrument made under it
(but
this subsection
does not affect any other legislation drawing meaning
from
Schedule 6
to
the 1981 Act
or amended by
Schedule 7
to
that Act
).
The 1981 Act is amended as set out in subsections (4) to (6) .
“4KA Acquisition by registration: persons connected with the former British
Indian Ocean Territory(1)
A person is entitled to be registered as a British citizen on an
application made under this section if—(a)
they were born before 23 November 2027,
(b)
they are a direct descendant of a person (“P”) who was a citizen
of the United Kingdom and Colonies by virtue of P’s birth in the former British Indian Ocean Territory or, prior to 8 November 1965, in the islands designated as the British Indian Ocean Territory on that date, and(c)
they have never been a British citizen.
(2)
An application under this section must be made—
(a)
in the case of a person born before 23 November 2004, before
23 November 2027;(b)
in the case of a person born on or after 23 November 2004,
before the day on which the person reaches the age of 23 years.”
Omit
section 17H
(entitlement to registration as British overseas territories
citizen for descendants of certain persons born in the British Indian Ocean
Territory).
“25A Limitation in respect of the British Indian Ocean Territory
Notwithstanding anything else in this Part, no person may become a British overseas territories citizen by descent by virtue of the British overseas territories citizenship of a parent if—
(a)
the parent’s citizenship was acquired by virtue of a connection
with the British Indian Ocean Territory, and(b)
at the time of the person’s birth, the parent would not, absent
that connection, have had or been entitled to acquire British overseas territories citizenship by virtue of a connection with any other territory.”
In consequence of the repeal made by subsection (5) —
in
section 4K
(1)
(a)
of
the 1981 Act
(entitlements giving rise to
entitlement to registration under that section), for “17F or 17H”
substitute “or 17F”;
in the
Nationality and Borders Act 2022
, omit
section 3
(insertion of
section 17H of the 1981 Act).
The repeals made by subsections
(5)
and
(7)
do not apply in relation to an
application under
section 4K
or
17H
of
the 1981 Act
made (but not determined)
before the day on which commencement falls; and nothing in this Act affects
the determination of such an application.
Nothing in this Act affects a person’s British citizenship or British overseas
territories citizenship acquired before commencement.
This section has the same extent as Part 1 of the 1981 Act .
His Majesty may by Order in Council—
make any provision that appears to His Majesty to be appropriate as
a result of the Treaty, and
make consequential, supplementary, incidental, transitional or saving
provision in relation to—
this Act, or
an Order under paragraph (a) .
An Order under
this section
may amend, repeal or revoke any legislation of
any of His Majesty’s dominions passed or made before commencement
(including legislation forming part of the law of Diego Garcia by virtue of
section
4
(1)
).
An Order under
this section
is subject to annulment in pursuance of a
resolution of either House of Parliament if it amends, repeals or revokes—
an Act, or
provision made under an Act by statutory instrument, other than an
earlier Order under
this section
.
This section does not limit the prerogative powers.
The exercise of the prerogative powers after commencement is not, as a result
of any provision of this Act or the Treaty, to be regarded—
for the purposes of the Foreign Jurisdiction Act 1890 (“the 1890 Act”),
as the exercise of powers in pursuance of that Act, or
for the purposes of section 1 (1) of the Statutory Instruments Act 1946 , as the exercise of powers conferred by this Act or the 1890 Act.
In
this section
, “the prerogative powers” means His Majesty’s powers under
his prerogative.
The Secretary of State must publish a statement setting out—
the total real terms cost of payments to be made to Mauritius under
the Treaty;
the full methodology and justification of the discount mechanism used
to calculate the total cost;
the methodology used to calculate the total cost of the Treaty by—
the Office for Budget Responsibility,
the Government Actuary’s Department, and
the Treasury.
The Secretary of State must, within the first financial year following the day
on which this Act is passed, lay before the House of Commons, for its
approval, an estimate of the expenditure that is anticipated to be incurred by
the Government of the United Kingdom in connection with the commitments
made under the terms of the Treaty, including, but not limited to—
any payments made or to be made, or financial commitments entered
into, with the government of the Republic of Mauritius in accordance
with the Treaty; and
the costs associated with the continued administration, maintenance,
and operation of Diego Garcia.
In each fifth successive financial year after the first financial year as set out
above, the Secretary of State must lay an estimate in accordance with
subsection
(1)
.
If at any stage during the operation of the Treaty the Secretary of State
presents to the House of Commons a report that the Republic of Mauritius
has, in his or her view, not honoured the provisions of the Treaty they have
undertaken to honour, and that the United Kingdom has presented to the
Joint Commission a reasoned case that it believes the Republic of Mauritius
has not honoured the provisions of the Treaty, and that the process in Article
14 of the Treaty has been exhausted, the Secretary of State must lay before
the House of Commons, for its approval, a resolution to cease payments in
connection with the Treaty.
This Act may be cited as the Diego Garcia Military Base and British Indian
Ocean Territory Act 2026.
A
bill
to
Give effect to, and make provision in connection with, an agreement between the governments of the United Kingdom and the Republic of Mauritius concerning the Chagos Archipelago.
Brought from the Commons on
Ordered to be Printed, .
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