Ryanair chief executive Michael O'Leary met some of the company's Dublin-based pilots last night in an attempt to end a bitter dispute over training for its new fleet of aircraft.

At a "townhall" style meeting, Mr O'Leary formally offered pilots the airline's terms for training to fly its new fleet of Boeing 737-800 series aircraft.

Ryanair has also requested that pilots, who have lodged more than 200 victimisation claims against Ryanair with the Labour Relations Commission (LRC), withdraw these claims as part of their training agreement.

Ryanair has given pilots until Friday to sign up to the terms for training or face the possibility that they may not be based in Dublin in the future.

The dispute erupted when Ryanair told its pilots last year that they would have to repay the €15,000 cost of the the training if the airline was forced to deal with a trade union within the five years.

The airline does not negotiate with trade unions.

Ryanair pilots subsequently submitted more than 200 claims of victimisation against Ryanair with the LRC.

The claims stem from correspondence and actions taken by Ryanair management on the issue of the conversion training for its Dublin-based pilots.

If all the victimisation claims were upheld by the LRC, Ryanair could potentially have to pay compensation of up to €52 million.

According to sources present at last night's meeting, Mr O'Leary adopted a more conciliatory tone than was usual at these types of "townhall meetings" with Ryanair staff.

In the past some Ryanair pilots have claimed that the meeting have been bruising affairs during which the chief executive has used foul and abusive language.

But a source at the meeting last night said that Mr O'Leary was extremely reasonable at the meeting and had uttered just one expletive during the entire 50 minute meeting under his breath.

Ryanair has offered to guarantee pilots who sign up to the new training regime a Dublin base.

However, the firm has also warned its pilots that they could face redundancy when the current Boeing 737-200 fleet is phased out unless they sign up for the new training.