US president Donald Trump said on Saturday that Washington could impose tolls on vessels transiting through the Strait of Hormuz if a final agreement with Iran is not reached, describing the potential charges as payment for US security services in the region.

Peace talks between the U.S. and Iran have faced significant friction this weekend as Iran said it shut down the Strait of Hormuz.

Peace talks in Switzerland could be off to a rough start, with Tehran warning that Israel’s attacks in Lebanon must stop.

Trump said Iran would not impose tolls in the Strait of Hormuz after the 60-day period outlined in the MOU.