The British government has reportedly not given the United States' permission to use its Air Force bases in the event of U.S. air strikes on Iran, multiple British outlets reported Thursday. 

President Donald Trump previously indicated that the U.S. could use Royal Air Force bases in Fairford, England, and in the British territory of Diego Garcia in the Indian Ocean, to conduct the strikes if Iran does not agree to curb its nuclear program.

It comes after Trump warned the United Kingdom not to complete its handover of the Chagos Archipelago, which includes Diego Garcia, to Mauritius amid heightened tensions with Iran, which The Times reports was prompted by the UK withholding permission to use the bases.

The British government declined to comment on whether it was withholding permission but said it supports the ongoing talks between the United States and Iran.

"There is a political process ongoing between the US and Iran, which the UK supports," the government spokesperson told the BBC. "Iran must never be able to develop a nuclear weapon, and our priority is security in the region."

The comment comes after Trump claimed the world would find out "over the next, probably, 10 days" whether the U.S. will reach a deal with Iran or take military action.

The U.S. has been building up its military presence in the area recently over the tensions with Iran, including by deploying multiple aircraft carriers in the region. Iran has warned that, if threatened, it will target U.S. military bases in the region.