The UK government said it "remains confident" a deal to give the Chagos Islands to Mauritius is the "best way forward", despite criticism from US President Donald Trump.
Foreign Office minister Stephen Doughty defended the agreement as he accused Conservative peers of using "parliamentary stunts" to try to "sabotage" legislation designed to confirm the treaty in UK law.
The government postponed Monday's House of Lords debate on the bill after Tory peers tabled an amendment calling for a pause "in light of the changing geopolitical circumstances".
Conservative shadow foreign secretary Dame Priti Patel said the delay showed "Labour's Chagos surrender humiliation continues".
Under the terms of the deal, the UK would give the Chagos Islands to Mauritius and pay to lease back the joint US-UK military base on Diego Garcia.
