(Bloomberg) -- Ryanair Holdings Plc will start mediated negotiations with Irish pilots on Monday in what may be the best chance yet of a breakthrough in a dispute over pay and contracts that’s hurting its earnings and disrupting travel for thousands of travelers.

The Forsa union, which represents Dublin-based Ryanair’s Irish flight crew, agreed to resume talks on Friday as its members joined a strike in five nations that led to the scrapping of flights due to carry more than 55,000 people.

While the industrial action is widespread, a breakthrough in Ireland is seen as key to resolving the increasingly bitter clash, since it was staff there who initiated the campaign for unionization and better employment terms. Ryanair had proposed mediation a week ago, suggesting Kieran Mulvey, a former chairman of the Irish Workplace Relations Commission, as an intermediary.

“Forsa’s focus will now shift to the negotiations,” it said, adding that Ryanair’s recognition of the need for an independent third-party facilitator had come too late to stop Friday’s strike. The meeting will mark the first time the two sides have sat down in the same room for 24 days, according to the union, which said there are no further plans for strikes right now.

The latest walkout, involving pilots from Germany, Belgium, Sweden and the Netherlands, as well as Ireland, led to the scrapping of more than 400 flights, according to Ryanair. That exceeds the 300 lost on two days last month when cabin crew in Spain, Italy, Portugal and Belgium walked out.

Ryanair said the majority of affected passengers have been accommodated on its other flights and that more than 2,000 services or 85 percent of the schedule operated as normal.

“We want to again apologize to customers affected by this unnecessary disruption and we ask the striking unions to continue negotiations instead of calling any more unjustified strikes,” it said by email. A spokesman declined to comment on the mediated pilot talks.

Friday’s action was the fifth by Ryanair’s Irish pilots, the prime movers in a campaign for unionization that was triggered when a rostering foul-up left the carrier short of air crew and forced the cancellation of 20,000 flights, giving staff a degree of leverage they’d never had before in its three-decade history..

Germany’s Vereinigung Cockpit pilot union has warned that more strikes are likely as it pushes Ryanair to improve salaries, acknowledge seniority and ease up on requirements for pilots to move between bases. Chief Executive Officer Michael O’Leary says the carrier can’t afford to jeopardize the low cost base that’s made it so dominant in Europe’s short-haul market.

Ryanair shares closed 4.2 percent lower in Dublin, taking the decline this year to almost 14 percent.

To contact the reporter on this story: Áine Quinn in London at aquinn38@bloomberg.net

To contact the editors responsible for this story: Anthony Aarons at aaarons@bloomberg.net, Christopher Jasper

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