Turkey's President Tayyip Erdogan left Qatar on Monday after two days in the Gulf trying to mediate in the worst row among Arab states for years but there was no sign he had made any progress.

Saudi Arabia, the United Arab Emirates, Bahrain and Egypt severed diplomatic and travel ties with Qatar in June, accusing it of supporting Islamist militants. Doha denies the claims.

Turkey has been Qatar's most powerful ally in the dispute, rushing through legislation to send more troops to its base in Doha as a sign of support.

Kuwaiti and Western efforts to end the crisis have yielded little so far. The four Arab states want Qatar to reduce ties with their arch-foe Iran, close down the Turkish military base and shut the Al Jazeera TV channel, which they view as critical of their governments.

Qatari state news agency QNA said that Qatar's ruler, Sheikh Tamim bin Hamad al-Thani, had "reviewed regional developments, specifically the Gulf crisis and efforts to contain it and to resolve it through diplomatic means..." in talks with Erdogan.

The agency said the talks also covered joint efforts to combat terrorism and reviewed defence and economic cooperation.

UAE Minister of State for Foreign Affairs Anwar Gargash said Qatar would achieve more by reconsidering its position.

"The Turkish president's visit did not carry anything new, and the hasty stand his country had taken made neutrality as the best option for Ankara" Gargash wrote on his Twitter account. "A Qatari review will achieve more than repeated visits."

Erdogan was the latest senior official to tour the region to try to resolve the crisis. U.S. Secretary of State Rex Tillerson and foreign ministers from France, Britain and Germany also toured the area in recent weeks.

Several contingents of Turkish troops with columns of armoured vehicles have arrived in Doha since the crisis erupted on June 5.

Under a 2014 agreement, Ankara could send in as many as 1,000 troops.

Turkey and Qatar have been important backers of the Muslim Brotherhood movement that has challenged entrenched Arab rulers and Erdogan has his roots in an Islamist political party.

Saudi Arabia and the UAE have designated the Brotherhood a terrorist organisation.

Before he arrived in Qatar, Erdogan visited Saudi Arabia and Kuwait. In Saudi Arabia, he discussed with King Salman "efforts to combat terrorism and its sources of funding", state news agency SPA said, without elaborating.