LOW cost airline Ryanair is pinning its hopes of bouncing back from a fall in first quarter profits on an end to the summer heatwave after passenger numbers were hit by the good weather.

The 21 per cent fall in the Irish carrier’s bottom-line figure, blamed on soaring fuel costs, the timing of Easter and a French air traffic control strike, had been expected.

But chief executive Michael O’Leary said performance in recent weeks has also been slightly weaker, which is believed to be a result of the heatwave in northern Europe.

He said while full-year profits were expected to remain as expected, this was on the basis that the weakness did not continue.

Mr O’Leary said Ryanair’s performance in the second quarter was still expected to improve, despite comparisons with the buoyant Olympic period last year.

He said the airline’s outlook remained cautious due to the recession and austerity measures, high fuel costs, and tax policies, but full-year traffic was expected to grow 3pc to 81.5million.

Ryanair, a major operator out of Stansted Airport, said its full-year profit after tax guidance remained at between 570 million euros (£492m) and 600m euros (£518m).

The airline’s first quarter saw passenger numbers up 3pc to 23.2m and revenue rising 5pc to 1.34bn euros (£1.16bn) — partly as a result of reserved seating, prority boarding and higher admin and credit card charges. Revenue per passenger rose 1pc but profit after tax fell 21pc to 78m euros (£67m).

Mr O’Leary said the airline’s seven new bases in Eindhoven, Maastricht, Krakow, Zadar, Chania, Marrakesh and Fez were performing well. He said new routes and bases would be announced later this year to exploit cutting back by other European carriers, while the airline was in negotiations with the new owners of Stansted airport to increase traffic.

He also used the announcement to criticise a Competition Commission decision which may force it to sell down its stake in rival airline Aer Lingus.

There has been nervousness in recent weeks about the impact of the heatwave on airlines’ performance, with hard-pressed passengers declining to shell out for a sunshine break abroad when they can top up on their tans at home.