Diego Garcia Military Base and British Indian Ocean Territory Bill — Bill 364 2024-26 (Lords Amendments)

Diego Garcia Military Base and British Indian Ocean
Territory Bill
LORDS AMENDMENTS
[The page and line references are to HL Bill 139, the Bill as first printed for the Lords]
Clause 1
1_ Clause 1, page 1, line 7, at end insert “, subject to subsection (2A).
(2A) Sections 2 to 4 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.”
2_ Clause 1, page 1, line 7, at end insert “, subject to subsection (2A).
(2A) Sections 2 to 4 of this Act come into force only when the conditions in section
(Referendum (No. 2)) have been met.”
After Clause 1
3_ After Clause 1, insert the following new Clause—
“Referendum (No. 2)
(1) Subsections (2) to (6) are the conditions of this section for the purposes of section
1(2A).
(2) Within six months of the day on which this Act is passed, the Secretary of State
must conduct a referendum of the Chagossian community.
(3) 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.
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(4) The question to be put to the Chagossian community in the referendum is stated
in subsection (5).
(5) The question is—
“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?”
(6) 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.
(7) In this section, “Chagossian community” means those Chagossians identified by
the Secretary of State who will be impacted by the Act.”
Clause 5
4_ Clause 5, page 3, line 41, leave out from “Parliament” to end of line 3 on page 4
After Clause 5
5_ After Clause 5, insert the following new Clause—
“Cost of the Treaty
The Secretary of State must publish a statement setting out—
(a) the total real terms cost of payments to be made to Mauritius under the
Treaty;
(b) the full methodology and justification of the discount mechanism used to
calculate the total cost;
(c) the methodology used to calculate the total cost of the Treaty by—
(i) the Office for Budget Responsibility,
(ii) the Government Actuary’s Department, and
(iii) the Treasury.”
6_ After Clause 5, insert the following new Clause—
“Parliamentary oversight and approval of expenditure
(1) 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
Diego Garcia Military Base and British Indian Ocean Territory
Bill

of the United Kingdom in connection with the commitments made under the
terms of the Treaty, including, but not limited to—
(a) 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
(b) the costs associated with the continued administration, maintenance, and
operation of Diego Garcia.
(2) 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).
(3) If the payments incurred by the Government of the United Kingdom are greater
than those anticipated in the estimate specified in subsection (1) or (2), the Secretary
of State must lay before the House of Commons, for its approval, a supplementary
estimate.
(4) 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.”
Diego Garcia Military Base and British Indian Ocean Territory
Bill

Diego Garcia Military Base and British Indian Ocean
Territory Bill
LORDS AMENDMENTS
Ordered, by The House of Commons,
to be Printed, 13 January 2026.
© Parliamentary copyright 2026, House of Commons
This publication may be reproduced under the terms of the Open Parliament Licence, which is published at www.parliam
ent.uk/site-information/copyright
PUBLISHED BY THE AUTHORITY OF THE HOUSE OF COMMONS
59/1 Bill 364