Gulf rivals Qatar and the United Arab Emirates traded accusations today over a complaint by Doha that an Emirati fighter jet had violated its airspace. <br/><br/>Qatar, which has faced a boycott by Arab states including the UAE since last June, said it had lodged a protest at the United Nations about the violation which allegedly took place on the 21st of last month. The UAE quickly denied the accusation.<br/><br/>Tensions have escalated in the Gulf since Saudi Arabia, the UAE, Bahrain and Egypt cut all ties with Qatar in June, largely isolating the emirate in the oil-rich Gulf.<br/><br/>The four countries accuse Doha of supporting Islamist extremists and being too close to Shiite Iran, Saudi Arabia's arch-rival. <br/><br/>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.