The U.S. faces a choice between launching an “impossible” military operation or accepting a “bad deal” with Tehran, Iran’s Islamic Revolutionary Guard Corps (IRGC) said Sunday, after President Donald Trump disparaged Iran's latest peace proposal.

Negotiations between the two countries have been deadlocked since a ceasefire came into effect on April 8, with only one round of direct peace talks held so far.

Iran's foreign ministry said Tehran had submitted a 14-point plan "focused on ending the war" and that Washington had already responded to it in a message to Pakistani mediators.

"We are reviewing this and will take whatever response is necessary regarding it," spokesman Esmaeil Baqaei told state television.

Trump, however, had already dismissed the offer.