Qatar's Amir on Tuesday publicly invited fellow Gulf rulers to a Doha summit, apparently seeking to forestall what diplomats say is an attempt by some peers to move it elsewhere in protest at what they see as an Islamist tilt in his foreign policy.
Diplomats say preparations for the annual gathering of the Gulf Cooperation Council (GCC) have become indicative of an unprecedented rift between Gulf Arab states over Doha's backing of Islamists during Arab Spring revolts.
In an unprecedented public move, Saudi Arabia, Bahrain and the United Arab Emirates recalled their ambassadors to Qatar in March, accusing Doha of failing to abide by an agreement not to interfere in one another's internal affairs.
So far efforts by members of the GCC, an alliance that also includes Oman and Kuwait, to resolve the dispute have failed.
In a speech to the advisory Shoura Council, Sheikh Tamim bin Hamad al-Thani said "deepening the bonds of brotherhood" among GCC members was at the forefront of Qatari foreign policy.
"In this context, we welcome our brothers the GCC leaders at a summit hosted by Qatar next month," he said.
The three states mainly fell out with Qatar over the role of Islamists, including the Muslim Brotherhood. Gulf officials say the three want Qatar to end any support for the Brotherhood, seen as a terrorist organization by Saudi Arabia.
Qatar says it backs all Arabs, not just Brotherhood members.
In comments likely to be heard disapprovingly by countries ranged against Islamic State, Sheikh Tamim said bombing militants in Iraq and Syria was not a solution. The problem had not just military but also political and social roots.
According to reports in regional Arabic media, the summit may be delayed or shifted to a new location in what analysts say would hurt the prestige of the influential gas exporting state.
"The UAE and Bahrain really don't want to come to Doha and have the emir chair the meeting, when they believe he hasn't done enough to resolve their conflicts," said an Arab diplomat in the Gulf.
"This is probably the most serious internal crisis that the GCC has faced since its creation," said Jean-Marc Rickli, assistant professor at the department of defence studies at King's College London based in Doha.