Sen. Bob Corker, R-Tenn., has blocked arms sales to nations in the Gulf Cooperation Council in a bid to push the Middle Eastern countries into seeking a solution to the diplomatic crisis with Qatar. They see Al-Jazeera as an arm of Qatari foreign policy, fomenting dissent.
Tillerson did not say - and neither has Qatar - which of the demands do and which do not meet his earlier-declared criteria of "reasonable and actionable".
That means it could affect huge chunks of President Donald Trump's planned $110 billion deal with Saudi Arabia, as well as other sales to the UAE, Qatar, Kuwait, Oman and Bahrain that the president has said he would welcome due to their potential benefit to the USA economy.
Tehran pledged to keep Iranian air space and sea routes open for Qatar to weather the blockade imposed on the tiny emirate by Saudi Arabia, Bahrain, the United Arab Emirates and Egypt. Ben Cardin, D-Md., said in a statement Monday that he shared Corker's concern, "the current GCC dispute distracts from our shared, most pressing security challenges", and that he would "continue to closely scrutinize all proposed foreign military sales based on a variety of issues and concerns".
"Gulf unity can only be restored when all countries involved are willing to discuss terms that are measured and realistic", he said.
The United States said the demands on Qatar by its Mideast neighbors "will be very hard to meet".More news: Italy giving 5.2B euros in resources to keep 2 banks open
The U.S. says some of the demands by four Arab countries as conditions to lift the sanctions over Qatar would be hard for Doha to meet.
Turkish President Recep Tayyip Erdoğan said the demands were in breach of worldwide law and said Ankara will not pull out troops from Qatar.
A productive next step would be for each of the countries to sit together and continue this conversation. "In their view, this is not how you treat close partners and pursue shared interests", she said.
It also demanded that Qatar close a Turkish military base in that country and sever ties with "terrorist organizations", including the Muslim Brotherhood. The deals includes naval vessels, helicopters, tanks and other major weapons systems that Trump has variously said would bring "thousands" and "tens of thousands" of defense industry jobs to the United States.
Tillerson also urged all sides to "lower" their rhetoric to ease tensions, and said that the U.S. would stay in "close contact" with all parties and support Kuwait in its mediation efforts.
"They did not come back to us since that day and even though they still didn't come back to us on this, asking Turkey to pull back its troops (from Qatar) is disrespectful against Turkey".