Ongoing restrictions on travel into the US have forced Aer Lingus to push out the start of its new transatlantic services from Manchester in the UK.
Flights to and from both New York and Orlando were due to begin on September 30.
But the New York service will not now begin until December 1 and the Orlando service until December 11.
A new three flights a week, non-stop service between Manchester and Barbados will start as planned on October 20.
The airline said it remains fully committed to the new Manchester transatlantic plans.
"Aer Lingus is sorry for any inconvenience caused and our dedicated teams are contacting customers directly to offer either a full refund, re-accommodation on an alternative service or the option of a voucher with an additional 10%, for use across the Aer Lingus network over the next five years," the airline said.
This is the second time that the launch of the transatlantic services from the UK have been delayed due to ongoing travel restrictions.
The airline had been hoping that the new routes would help boost its recovery in the wake of the pandemic.
Regulators in the UK cleared Aer Lingus to begin operating the service a couple of weeks ago.
Since March of last year, non-US nationals or permanent residents have not been allowed to travel to the US if they have been in Ireland, the UK, the Schengen zone or a number of other countries during the previous 14 days.
However, US citizens and permanent residents, certain specified close family members and certain other limited categories of visas holders are exempt from these restrictions and can still enter the US, subject to normal requirements.
Earlier this month it was reported that the US government was developing a plan to require nearly all foreign visitors to the United States to be fully vaccinated against Covid as part of a plan towards eventually lifting travel restrictions.