Malaysia Flight 17's route FlightAware MH17 flight feared to have been shot down over Ukraine was taking a significantly different route to the usual course for flights from Amsterdam to Kuala Lumpur, according to aviation expert.

The crashed MH17 flight took a route 300 miles to the north of its usual path, an aviation expert has said.

Robert Mark, a commercial pilot who edits Aviation International News Safety magazine, said that most Malaysia Airlines flights from Amsterdam to Kuala Lumpur normally travelled along a route significantly further south than the plane which crashed.

Malaysia Airlines has insisted its plane travelled on an "approved route" used by many other carriers.

But Mr Mark said: "I can only tell you as a commercial pilot myself that if we had been routed that way, with what's been going on in the Ukraine and the Russian border over the last few weeks and months, I would never have accepted that route.

"I went into the FlightAware system, which we all use these days to see where airplanes started and where they tracked, and I looked back at the last two weeks' worth of MH17 flights, which was this one.

"And the flight today tracked very, very much further north into the Ukraine than the other previous flights did ... there were MH17 versions that were 300 miles south of where this one was."

Records of recent MH17 flights on the FlightAware appear to bear out Mr Mark's claim, with earlier flights significantly further south than the flight that crashed.

Mr Mark’s intervention came amid mounting questions over why passenger jets were flying over the war zone three months after pilots were warned to avoid it.

Aviation safety authorities in America and Europe warned pilots in April about potential risks flying in or near Ukraine airspace.

However experts claimed that operators continued to fly across the zone because it was the quickest and cheapest route for some flights.

Norman Shanks, a former head of group security at the BAA airports group, said: "Malaysia Airlines, like a number of other carriers, has been continuing to use it because it is a shorter route, which means less fuel and therefore less money."

Attacks on aircraft in the area have been rife. In the past week alone two Ukrainian military aircraft were shot down and a third was damaged by a missile.

Eurocontrol, which coordinates European air traffic control, said Ukrainian authorities had now closed all routes in the east of the country.

A spokesman for Malaysia Airlines said: "This route is an approved route. 15 out of 16 airlines use this route. It's a safe route - most other countries use this route.

"So we were not given any notice to change this."