Taking initiative to resolve the Gulf crisis Turkish Foreign Minister Mevlut Cavusoglu has landed in Doha in a first leg to his Gulf tour to mend Qatar's ties with Arab states and said the crisis should be resolved "through peace and dialogue".

As the Saudi-led bloc moved against Qatar, the US Secretary of State Rex Tillerson's attempts to remain neutral were overshadowed by a series of heavy handed Tweets from Trump, in which he accused Qatar of supporting "terror".

"The secretary and the minister also discussed mutual security interests, including the current status of operations against IS (Islamic State), and the importance of de-escalating tensions so all partners in the Gulf region can focus on next steps in meeting common goals", Cabiness added.

The deal is for reportedly for 36 jets, after the Obama administration approved a possible sale for up to 72 jets for $21.1 billion a year ago.

The U.S. military announced a similar $21.1 billion deal in November, in the waning days of the Obama administration, for 72 F-15QA fighter jets for Qatar, the Associated Press reported.

A few weeks ago America also sealed a deal with Saudi Arabia, selling them weapons worth $100 billion (£78.4 billion). Boeing, the prime contractor on the sale, declined to comment.

Meanwhile, the United Nations human rights chief Wednesday warned of possible human rights violations in the wake of the diplomatic and economic isolation of Qatar.

A Saudi-led blockade imposed against Qatar raised fears of a food crisis in Qatar, as most of its supplies come from Saudi Arabia and the United Arab Emirates.

Cavusoglu will hold a bilateral meeting with his Qatari counterpart, Sheikh Mohammed bin Abdulrahman bin Jassim Al-Thani, Turkish foreign ministry said in a statement late Tuesday.

The purchase is expected to increase Qatar's capability, improved security cooperation and interoperability between the two allies, a spokesman for Pentagon Lt. Col. Rogers Cabiness briefed CNN. Mattis formerly oversaw the U.S. military's Central Command, whose forward operating base is at the vast al-Udeid air base in Qatar.

"We see it as a tangible show of support for our defense relationship and their commitment to the United States", spokeswoman Heather Nauert told reporters.

On June 5, Saudi Arabia, Bahrain, the United Arab Emirates and Egypt cut diplomatic ties with Qatar and embargoed all sea, air and land traffic to the country, accusing Doha of supporting terrorists and destabilizing the Middle East, and several other states of the region reduced diplomatic relations with the country. The foreign ministry said foreign affairs minister Youssef bin Alawi called for support of Kuwaiti mediation efforts as the best chance for resolving the crisis. Bahrain and the UAE have also made illegal expressions of sympathy for Qatar.

Indeed, Trump publicly condemned Qatar - where 10,000 American troops are stationed - for funding "terrorism at a very high level".