US state department says Washington is concerned impasse with Saudi-led quartet of countries could drag on for months

Mohammed bin Abdulrahman al-Thani, the Qatari foreign minister, meets Rex Tillerson in Washington DC on 27 June.
Mohammed bin Abdulrahman al-Thani, the Qatari foreign minister, meets Rex Tillerson in Washington DC on 27 June. Photograph: Shawn Thew/EPA

The US secretary of state will fly to the Gulf on Monday as the US steps up efforts to end a crisis in which a Saudi-led quartet of Arab countries have embargoed Qatar over what they say is its support for terrorism.

Rex Tillerson will fly to Kuwait, which has tried to mediate between the two sides, after Saudi Arabia and its allies warned of new steps against Doha as a deadline for action passed without the standoff being resolved.

A US state department spokeswoman said Washington was growing “increasingly concerned that the dispute is at an impasse” and could drag on for months.

Tillerson will arrive in Kuwait hard on the heels of the British foreign secretary, Boris Johnson, who arrived in the region on Friday on his own mediation mission.

The US defence secretary, James Mattis, called his opposite number in gas-rich Qatar, Khalid bin Mohammad al-Attiyah, to emphasise the “importance of de-escalating tensions … so all partners in the Gulf region can focus on next steps in meeting common goals,” the Pentagon said.

The two officials “affirmed the strategic security partnership” of their countries. The US stations 10,000 troops at a huge airbase in Qatar that is vital for the campaign against Islamic State.

Germany has also offered the help of its intelligence services to clear up allegations of Qatari funding of extremism.

The moves came as the four Arab countries isolating Qatar vowed to take additional steps after Qatar refused to accept a list of 13 demands – which include shutting down the cable news network al-Jazeera, based in Doha.

In a joint statement carried on Gulf state media, Saudi Arabia, the United Arab Emirates, Egypt and Bahrain accused Qatar of blocking all efforts aimed at resolving the rift, adding that Qatar intends to “continue its policy aimed at destabilising security of the region”.

They vowed to “take all necessary political, economic and legal measures” against Qatar in a “timely manner”. They did not specify what those steps could include, though officials have previously suggested they could intensify efforts to isolate Qatar economically.

The four countries cut diplomatic ties and severed air, land and sea links with the World Cup 2022 host early last month. They later issued a 10-day ultimatum to a 13-point list of demands that included cutting ties with terrorist groups, curbing relations with Iran and shutting media outlets.

On Friday Qatar again denied links to extremism and dismissed the allegations against it as baseless.

“The State of Qatar’s position on terrorism is consistent and known for its rejection and condemnation of all forms of terrorism, whatever the causes and motives,” the state news agency said, quoting a senior foreign ministry source.

It added that Qatar remains ready to “cooperate and review all claims that do not contradict the sovereignty of the state of Qatar”.

Despite the embargo, Qatar has proved more resilient than the Saudi-led quartet appears to have anticipated, quickly shifting its port arrangements and attracting the prominent support of Turkey.

Qatar issued its response to the ultimatum in a handwritten letter from 37-year-old emir Tamim bin Hamad al-Thani that was delivered to Kuwait earlier this week. The contents of the letter have not been disclosed, but the anti-Qatar bloc has described it as negative and failing to appreciate the gravity of the situation.

Qatar denies it sponsors extremism and says the moves against it are aimed at stifling a foreign policy that has carved a more independent route than its Gulf neighbours on Iran – with whom Qatar shares a gas field – and during the Arab spring.

Qatar has also been criticised for its connections with the Muslim Brotherhood and for hosting senior members of the Palestinian Islamist movement, Hamas.

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