A Ryanair jet
A Ryanair jet reclines on the tarmac Reuters

Ryanair is planning to cut the number of flights it operates from London's Stansted Airport by 9 percent over the next year due to increased fees.

The company was to increase the number of flights to and from the Essex airport by 5 percent from April, but will now cut 170 flights across 43 routes a week.

The Irish airline accounted for about 70 percent of Stansted's traffic in 2011, and a reduction in the number of flights would result in up to 1,000 job cuts.

The announcement came after Stansted airport was acquired by Manchester Airports Group (MAG) from Ferrovial/BAA for £1.5bn, (€1.7bn, $2.3bn).

The low-cost carrier said that the airport's decision to increase charges by 6 percent should be investigated by the Civil Aviation Authority (CAA).

"It's bad enough that Ferrovial/BAA has doubled prices over the past six years and presided over record traffic falls at Stansted, but it appears that the CAA now rewards this commercial failure by allowing Ferrovial/BAA to again raise fees in 2013 to compensate for its traffic declines in 2012," said Ryanair spokesman Robin Kiely.

"Ryanair and other Stansted airlines now must ask was this surprise price increase part of a sweetener package to persuade MAG to pay £1.5bn for Stansted."

Several UK airports including, Stansted, Gatwick and Heathrow negotiate price increases every five years.

Both Gatwick and Heathrow recently submitted their proposals for landing charges over the period between 2014 and 2019.

"As part of our plans to grow passenger volume at Stansted over the short, medium and long term, we will continuously engage with all of the airlines that operate there, many of which are already valued customers of ours," the Telegraph quoted an MAG spokesman as saying.