Ryanair will add an extra daily frequency on each of five UK-Ireland routes from this winter, as it bids to raise the pressure on its rival Aer Lingus.
From October, the low-cost carrier is to add "at least" one extra daily service on routes from Dublin to Birmingham, Bristol, Edinburgh, London and Manchester, mirroring Aer Lingus's recent increases in frequencies.
Chief executive Michael O'Leary says the additional flights provide fresh evidence of "intensified competition" for the UK Competition Commission, which next month will rule on whether Ryanair must divest its near-30% stake in Aer Lingus.
The rising frequencies by both carriers comes despite Aer Lingus chief Christoph Mueller saying that "weakness in UK routes, identified in our Q1 results, has continued in Q2", and citing this as a contributing factor in a half-year operating loss of €16.4 million ($21.7 million).
Flightglobal's FlightMaps Analytics data shows that in all markets Aer Lingus continues to offer more frequencies than Ryanair.
In the Dublin-London market, Aer Lingus will in November operate 601 services, a 37% share of the market, compared with 449 flights by Ryanair, which has a 27% share.
On the Birmingham-Dublin route, Aer Lingus will have a 67% share of frequencies compared with Ryanair's 33%, while the Irish flag carrier also dominates on Manchester-Dublin, with 53% of frequencies; Edinburgh-Dublin, with 66%; and Bristol-Dublin, with 55%.