US President Donald Trump and British Prime Minister Keir Starmer have agreed to work “closely” to maintain the key Diego Garcia military base in the Indian Ocean following recent criticism by Trump of UK action, the prime minister’s office said Tuesday.

The US president said last month that Britain had been wrong to give the Chagos islands, which includes Diego Garcia, back to Mauritius. The islands had been at the centre of a decades-long diplomatic battle. Trump had earlier endorsed the accord.

The base was discussed in a telephone conversation between Trump and Starmer that Downing Street reported on late Tuesday.

“The leaders agreed their governments would continue working closely to guarantee the future operation of the base and speak again soon,” the prime minister’s office said.

Under the deal agreed in May last year, Britain will hand back the Chagos islands to Mauritius but keep the Diego Garcia base, jointly run by US and British forces, on a 99-year lease.