Oil prices inched up and stocks dipped on Sunday as the status of the Strait of Hormuz remained unclear, underscoring how challenging it may be to restore energy flows through the region.

Traffic through the narrow waterway appeared to dip after Iran’s military said on Saturday that it was closing the strait over Israel’s continued fighting in Lebanon. The U.S. Central Command disagreed, saying the shipping route remained open.

The reality remained murky on Sunday, when Iran and the United States met in Switzerland for a first round of negotiations aimed at converting a 60-day cease-fire between the countries into something more permanent. The countries have a big gap to close in future negotiations.