President Donald Trump said he may not extend a tentative ceasefire between the United States and Iran if negotiations fail to produce an agreement by Wednesday, raising the prospect of renewed military action.

“Maybe I won’t extend it,” Trump said when asked aboard Air Force One whether he would prolong the ceasefire or resume strikes if talks fall short.

“Maybe I won’t extend it, so you have a blockade, and unfortunately we have to start dropping bombs again,” the president added.

The comments come as US and Iranian delegations are expected to arrive in Pakistan this weekend and potentially hold negotiations Monday, according to Iranian sources familiar with the talks. The United States has not confirmed whether those meetings are scheduled.

Trump expressed confidence earlier Friday that the parties are close to a deal.