The United Arab Emirates accused rival Qatar of "intercepting" two Emirati passenger planes en route to Bahrain Monday in the latest incident between the Gulf rivals.
Qatar denied that the first plane had been intercepted, but there was no immediate denial from Doha for the second incident.
The UAE "General Civil Aviation Authority received a message from a national carrier on Monday morning that an aircraft on a routine flight to Manama was intercepted by Qatari fighter jets", it said in a statement carried by the state news agency.
The authority said it was "a flagrant and serious threat to the safety of civil aviation and a clear violation of international law".
"This is a routine flight that has all the required paperwork," it said.
The authority later said a second Emirati passenger plane bound for Bahrain was also intercepted by Qatari fighter jets.
It said the second plane was intercepted "during its descent towards Bahrain International Airport", adding that it was also on a routine pre-scheduled flight.
A spokeswoman for Qatar's foreign ministry denied the first incident had occurred.
"The state of Qatar announces that the claims of Qatari fighter planes intercepting a UAE civil aircraft (are) completely false," Lulwa al-Khater said on Twitter.
Four UAE-based airlines - Emirates, Etihad, flydubai and Air Arabia - operate flights to Bahrain.
Spokespersons for the airlines contacted by AFP could not immediately confirm or deny the news.
Monday's allegations came after Qatar accused UAE fighter jets of violating its airspace in December and January.
Qatar is located in the Gulf, between Bahrain and the United Arab Emirates and across the Gulf waters from Iran.
Tensions have escalated in the Gulf since Saudi Arabia, the United Arab Emirates, Bahrain and Egypt cut all ties with Qatar in June, accusing Doha of supporting Islamist extremists and being too close to Saudi Arabia's arch-rival, Iran.
They have banned all flights to and from Doha and cut off most trade links.
Qatar denies the allegations, arguing the bloc aims to incite regime change in Doha.For all the latest transport news from the UAE and Gulf countries, follow us on Twitter and Linkedin, like us on Facebook and subscribe to our YouTube page, which is updated daily.
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