DUBLIN (Reuters) - Ryanair said on Thursday it would buy back up to 800 million euros ($872.48 million) more of its shares over the next six to nine months due to a stronger than expected cash position, driven partly by the delayed delivery of new Boeing ( BA ) aircraft.

The Irish airline, Europe's largest by passenger numbers, announced a 700-million-euro share buyback in May, its first since the COVID-19 crisis and said on Thursday that would be completed by the end of August.

Ryanair said that while airfares had softened more than expected recently, it decided on the follow-on buyback after a boost to cashflow from strong traffic growth and the delivery delays which "considerably delayed planned capital expenditure."

Ryanair shares spiked higher after the announcement and finished the day up 4.4%.

Ryanair said last month that Boeing ( BA ) had warned it that some 737 MAX deliveries due by next spring would be delayed until the peak summer months of 2025 - a repeat of delays this year that forced a cut in its summer traffic volumes.

Ryanair also said on Thursday that its board will seek shareholder approvals at its AGM in September to increase its annual buyback authority from 10% of issued share capital, to up to 15%.

With no new aircraft deliveries scheduled from mid-2025 to mid-2027, Ryanair said it expects cashflow to receive a short term boost and create the capacity to extend shareholder returns. Deliveries are due to increase sharply again from late 2027.

($1 = 0.9169 euros)