BUDGET airline easyJet said it saw passenger numbers soar by nearly a quarter last month, but warned that the outlook remained uncertain.

EasyJet carried 2.08 million people in January, 23.8 per cent up on the 1.68 million in the same month last year. In the three months to December, passenger numbers increased 26 per cent to 6.7 million.

The carrier said it had experienced a sound first quarter and that the second quarter was positive so far.

However, the company said market visibility remained limited and that the second quarter outcome would depend on the Easter period.

Chief executive Ray Webster said the company was basing yield forecasts in its longer term business plan - the amount of money it makes per customer - on an outlook of continued intense competition.

EasyJet's load factor - how full its aircraft were - fell 0.8 per cent to 76.4 per cent last month. For the three months to December, the load factor rose 0.6 to 83 per cent.

Total revenues for the 12 months to January increased by 18.7 per cent while total revenue per passenger in the three months to December fell 0.8 per cent to £41.87m.

The carrier flies more than 150 routes after adding services in the past year to cities including Basle, Budapest and Dortmund.

However, competition in the European low-cost sector has become intense, with at least 47 low-cost airlines now operating in Europe, compared with only seven three years ago.

As well as tough competition from low-cost rivals such as Ryanair, bmibaby and Air Berlin, easyJet is facing pressure from increased fuel costs.