Republican presidential candidate Donald Trump appears to have softened his stance on temporarily barring Muslims from travelling to the US.
Responding to remarks by London Mayor Sadiq Khan, Mr Trump told Fox News Radio the ban was "just a suggestion".
Mr Khan has expressed concern that he would not be able to travel to the US under a Trump administration because of his Muslim faith.
Mr Trump had offered to make an "exception" for Mr Khan.
Mr Khan refused Mr Trump's offer, saying the New York businessman's views were "ignorant" and would make the UK and the US "less safe".
Mr Trump proposed a ban on Muslims entering the US after attacks in Paris killed 130 people last year.
The suggested ban has been widely criticized in the US and abroad but Mr Trump until now has stood by the proposal, saying it was needed to ensure US security.
"It's a temporary ban. It hasn't been called for yet," Mr Trump said on Wednesday. "This is just a suggestion until we find out what's going on."
Mr Trump has shifted positions in the past on a variety of issues only to change his stance days later, foreign media reports.