The countries agreed in 2017 to restore diplomatic representation after boycotting and embargoing Qatar.
The UAE and Qatar have announced the reopening of their embassies after a six-year-long shutdown.
The two countries issued statements on Monday saying the Qatari embassy in Abu Dhabi and a Qatari consulate in Dubai and an Emirati embassy in Doha had resumed operations.
The statement did not say whether the ambassadors were stationed or whether the missions were open to the public.
Qatar said the foreign ministers of the two countries spoke by phone to congratulate each other on the reopening of diplomatic missions.
“The UAE and the State of Qatar have announced the restoration of diplomatic representation between the two countries,” said a statement by the UAE’s official WAM news agency.
The UAE joined Saudi Arabia, Bahrain and Egypt in 2017 in boycotting and imposing a blockade on Qatar over what it called Doha’s support for “terrorist” groups and its growing closeness to Iran. Qatar has strongly denied all the allegations.
Qatar has faced an unprecedented diplomatic crisis due to its gas resources and close ties with Turkey and Iran.
The boycott was officially lifted in January 2021. Late last year, Qatar welcomed visiting leaders from Saudi Arabia, Egypt and the United Arab Emirates as it hosted the FIFA World Cup.
Easing the Gulf Rivalry
Turkey, which threw its weight behind Qatar during the crisis, has since mended relations with rival Gulf states, including the United Arab Emirates and Saudi Arabia.
Saudi Arabia and Iran announced the end of a seven-year truce in March after diplomatic missions eased tensions in the Gulf.
A round of reconciliation followed, with Qatar and Bahrain resuming ties in April.
Saudi Foreign Minister Faisal bin Farhan visited Iran on Saturday, meeting with President Ibrahim Raisi in another major step in their rapprochement. Iran has opened an embassy in Riyadh this month.
The wedge between Riyadh and Tehran appears important as they have long struggled for influence around the region, backing opposing sides in conflicts including Yemen.
Last month, the Arab League brought Syria back into its fold after 12 years.