US Defence Secretary Jim Mattis arrived in Oman on Sunday (March 11th) ahead of a meeting with Sultan Qaboos to discuss ongoing security concerns, including the situation in neighbouring Yemen, AFP reported.
Mattis's visit, his first as Pentagon chief, comes amid regional strains over the Yemen conflict and a diplomatic rift between Qatar and a bloc of countries led by Saudi Arabia.
"The unity of the (Gulf Co-operation Council) has been strained, to put it mildly, so I am also wanting to hear what the sultan says can be done about that, as well as the situation on his border in Yemen with the various factions that are fighting there and certainly the civil war," Mattis said.
"The Gulf's cohesion is critical we believe to maintaining stability in the region."
Under Qaboos, the longest-serving ruler in the Arab world, Oman has maintained good ties with countries outside the six-country GCC bloc to which it belongs, including neighbouring Yemen.
In March 2015, the sultanate was the only GCC country not to join the Arab coalition's air war on the Iran-backed Houthis (Ansarallah) in Yemen, but also maintained solid relations with Riyadh.
Mattis was slated to meet with Oman's defence minister Monday and other senior Omani officials.