Iran and the United Arab Emirates (UAE) have signed a memorandum of understanding (MoU) to “promote cooperation on common border security”, Tasnim News Agency has reported.

The signing came after a meeting between Iranian military and UAE Coast Guard officials—and the very fact that the meeting even took place may be an indication that emirate business hubs are growing nervous about potential impacts from the showdown between Iran and the US and its Middle East allies. The security of shipping in the Gulf, for instance, is becoming increasingly uncertain following limpet mine attacks on oil tankers—blamed on Iran by the US, but nothing to do with Iran according to the Iranians—and Iran’s seizure of the British-flagged, Swedish-owned Stena Impero oil tanker. The US is trying to persuade European allies to help form a naval mission that would escort tankers through waters including the Strait of Hormuz and Sea of Oman.

The MoU was according to Tasnim—a news service linked to Iran’s Islamic Revolutionary Guard Corps (IRGC)—signed by the Commander of Iran's Border Police, Brigadier General Qassem Rezaei, and UAE Coast Guard Commander Brigadier General Mohammed Ali Musleh Al-Ahbabi.

The finer details of the agreement were not released, but it could be related to the safe passage of Emirati vessels transiting the Strait of Hormuz, the world’s busiest chokepoint for energy shipments.

Rezaei reportedly said that such meetings between Iran and the UAE “contribute to stronger border security” and “facilitate legal border crossings and the activities of fishermen, and help fight against those disrupting the security of nations”.

For his part, the Emirati commander hailed the meeting with “Iranian friends”, describing the agreement with Iran as a positive step in “fulfilling the interests of the two countries”.