Sen. Bob Corker (R-Tenn.), chairman of the Senate Foreign Relations Committee, intends to block future weapons sales to Persian Gulf countries until the region solves its dispute over Qatar’s alleged support for extremist groups.

Corker’s decision, included in a June 26 letter addressed to Secretary of State Rex Tillerson, will stop significant arms sales to Gulf Cooperation Council (GCC) nations such as Qatar, Saudi Arabia and the United Arab Emirates. As Foreign Relations Committee chairman, Corker has authority over the approval of arms sales to foreign countries before proposed deals are sent to Congress for review.

“I could not have been more pleased with the President’s recent trip to Saudi Arabia. The unity of the Gulf States and their commitment to security cooperation were welcome steps forward,” Corker said in his letter. “Unfortunately, the GCC did not take advantage of the summit and instead chose to devolve into conflict.”

The senator cited a lack of focus among Gulf nations in the efforts to counter Iran and push back against ISIS as his impetus for reviewing further deals of lethal military equipment to the region. The six nations of the GCC have had ongoing internal disputes over Saudi-led pressure on the Qatari government to end its alleged funding of terrorism and ties with Iran.

“For these reasons, before we provide any further clearances during the informal review period on sales of lethal military equipment to the GCC states, we need a better understanding of the path to resolve the current dispute and reunify the GCC,” Corker said.

Corker’s announcement to block arms sales comes after President Trump’s recent announcement of a possible $110 billion arms deal with Saudi Arabia. However, this decision will not affect the previously approved $500 million arms deal with Riyadh which avoided a bipartisan bill to block the deal in the Senate after a 47-53 vote in May.