New Delhi, May 13 -- U.S. President Donald Trump on Monday said the Iran ceasefire is on "life support" after rejecting Tehran's latest proposal, which officials said included some nuclear concessions. Trump also proposed suspending the federal gas tax to help with higher fuel prices caused by the war.

The stalled diplomacy and recent exchanges of fire could tip the Middle East back into open warfare and prolong the worldwide energy crisis sparked by the conflict. Iran still has a chokehold on the Strait of Hormuz, a vital waterway for global oil and gas shipments, and America is blockading Iranian ports.

Asked at the White House if the ceasefire was still in effect, Trump said it's on "life support."

"I would call it the weakest right...