(Reuters) - British Airways has extended its suspension of flights to the Egyptian resort of Sharm al-Sheikh indefinitely, becoming the first major UK airline to cancel departures for the crucial winter season in Egypt.

British and Russian governments banned their airlines from flying to Sharm al-Sheikh, a popular winter sun destination, because of concerns about security at the local airport after the suspected bombing of a Russian passenger jet in October 2015 killed all 224 people on board.

Tourism is a key source of income for the Egyptian economy but the number of tourists fell 40 percent in the first quarter of 2016, partly hurt by the flight ban keeping British and Russian tourists away.

"The safety and security of our customers will always be our top priorities and we have suspended our flights from Gatwick to Sharm al-Sheikh indefinitely," British Airways said in a statement on Tuesday.

Customers with bookings on any cancelled services for the winter season will be offered a full refund or can put the money towards a new flight to an alternative destination, it added.

Other British airlines, such as Monarch and easyJet, have previously said they hoped to restart flights to Sharm al-Sheikh for the winter season beginning in October, although that is dependent on advice from the UK government, which has so far not changed.

Egyptian tourism minister Yehia Rashed last month called on the British and Russian governments to rethink their position on the flight ban.

Egypt's efforts to revive its tourism industry suffered a fresh blow in May when an EgyptAir plane crashed into the Mediterranean, killing all 66 people on board. The cause of the crash is still unknown.

Monarch has cancelled all flights up to October 30, easyJet for the rest of the summer season, while tour operators Thomson and First Choice, part of the TUI Group, have cancelled until Sept. 28.

"Should the travel advice change prior to 30 October, Monarch will reassess the situation and decide when to restart services to Sharm El Sheikh," Monarch said.

(Reporting by Victoria Bryan; Editing by Keith Weir)