Passengers demanding compensation for delayed flights are being “fobbed off” or turned down by some of the biggest airlines.

Ryanair refused to pay out on nearly half the claims sent in by its customers for delays over three hours, a poll suggests.

The airline rejected 48% of applications – a higher proportion than any other airline in the study of more than 3,000 passengers.

Virgin Atlantic was next, spurning 36% of claims, the Sunday Mirror reported.

Some passengers have been left waiting as airlines put off processing their requests. Jet2 is the worst for stalling, with decisions pending on 63% of claims – closely followed by Thomson, with 61% still waiting for a payout decision.

Thousands of such claims have been submitted by passengers since the European Court of Justice ruled last October that delays of more than three hours merited compensation of up to £510. The ruling could potentially cost airlines millions of pounds.

But research by reveals which airlines are paying out and which are rejecting or sitting on claims.

Some carriers blame technical faults or “exceptional circumstances” outside their control, discouraging people from pursuing claims.

The newspaper’s consumer rights expert Dean Dunham said: “Airlines are trying to wriggle out of claims. They have failed to tell passengers their rights or simply fobbed them off with complicated legal excuses why they are not entitled to claim.”

Virgin Atlantic insisted it processed all claims in accordance with Civil Aviation Authority guidelines.

A spokesman said: “We aim to respond to passengers within 12 weeks, although in some circumstances, further investigation may be needed, causing a slight delay.”

Monarch Airlines said: “All claims submitted to us are resolved within 28 days. The ‘pending figure’ will therefore be made up of claims made within the last 28 days.”

A Jet2 spokesman said: “This poll demonstrates that, as EU legislation currently stands, neither customers nor the airline industry have clarity on the situation. Our priority is to provide a friendly service at a great value price.”

A Ryanair spokesman said: “Ryanair complies fully with EU261 legislation and 99% of passenger complaints are answered within seven days.”