(Bloomberg) –Qatar said its emir has been invited by the Saudi monarch to attend this month’s summit of Gulf Arab nations in Riyadh, in what would be a major breakthrough in intensifying attempts to end a 30-month feud.

Saudi Arabia, the United Arab Emirates, Bahrain and Egypt cut diplomatic and trade links with Qatar in 2017 after accusing the gas-rich state of building close ties with their chief regional foe, Iran, and funding militant groups. Qatar has repeatedly denied the charges.

King Salman’s written invitation was delivered to Qatar’s foreign minister by the secretary-general of the six-nation Gulf Cooperation Council, the official Qatar News Agency reported. The country’s ruler, Sheikh Tamim bin Hamad Al Thani, hasn’t yet responded to the invitation.

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Last week, the three boycotting Gulf states sent national teams to play in the 2019 Arabian Gulf Cup in Qatar after a last-minute decision to take part.