US President Donald Trump on Sunday rejected Iran’s response to Washington’s latest peace proposal, calling it “totally unacceptable.”

Tehran didn’t resolve the US’ demands over its nuclear program, The Wall Street Journal reported. Trump’s rejection is set to prolong the countries’ uneasy stalemate in the Strait of Hormuz.

Tensions flared in the Gulf over the weekend, as the UAE, Kuwait, and Qatar all reported attacks from Iranian drones; a strike also briefly set a ship ablaze.

But there was some indication of diplomatic progress to ease global supply concerns.

A Qatari liquefied natural gas shipment transited the strait for the first time since the beginning of the war, following talks between Iran, Qatar, and Pakistan.