After four days of attacks back and forth between Iran and the U.S. in the Persian Gulf, ship traffic through the Strait of Hormuz has dropped significantly again.

According to The New York Times, before the weekend, shipping traffic through the strait had risen to its highest levels since March 1, with many ships taking a U.S.-backed route that bypassed Iranian waters. But, in light of the renewed dangers, some shipowners have decided it was too risky to transit.

On June 25, Iran renewed its demand that ships use its waters, and obtain permits to go in or out of the strait, warning that other routes were “unacceptable and extremely dangerous.” Then Iranian forces attacked a container ship in Omani waters, the U.S. conducted retaliatory strikes, and Iran attacked a second ship, a Panama-flagged tanker called the Kiku, on June 27, according to the U.S. Central Command. 

According to a U.S. official, the U.S. and Iran have agreed to halt their attacks and allow vessels to move freely as of June 29. But Iranian officials had not confirmed that an agreement had been reached.

According to data from Kpler, a maritime tracking firm, 22 ships passed through the strait on June 28, down from 38 on June 27. 

CMA CGM, on June 28 said that it was pleased to announce that its containership CMA CGM Galapagos had passed through the strait via Iranian waters that morning, according to Maritime Executive. “This transit marks an important milestone in a regional context that remains complex and requires constant vigilance,” the company said.

A plan announced last week by the International Maritime Organization to evacuate some 600 ships and 11,000 seafarers stranded in the strait remained paused on June 29. The agency had helped get some 115 vessels out before it suspended the program on June 25.

Iran continues to assert that the only route is its corridor and that all vessels require its permission, regardless of any agreements.

“Any attempt to adopt new or separate arrangements from those currently being pursued by the Islamic Republic will only lead to further complications, delays in reopening the Strait of Hormuz, and an increase in tensions,” said Iran’s foreign minister, Abbas Araghchi, in a news conference on June 28.