The move comes despite the announcement this week that the airport had agreed a deal with Omni Air International which should see 100 extra military flights pass through the airport each month.

At the moment, the SAA operates its duty free store on a 24-hour basis to cater for the flights, which tend to use the airport between 11pm and 6am each night when there are no scheduled passenger flights.

However, the numbers of military flights through the airport have fallen dramatically in recent months and the SAA's recent agreement with staff over cost-cutting contained provisions for closing its retail operations at night.

Under the provisions, the airport's temporary retail staff would be let go while the issue of permanent staff redundancies would be dealt with "using all available industrial relations procedures as necessary".

The chairperson of the Clare County Development Board, Patricia McCarthy, said that the board felt that the proposals were a major step backwards for the airport's development. She said the board wanted the SAA to expand the range of services it offered at night.

"It is an advantage that Shannon has that no other Irish airport has. It's a very good marketing tool to have, particularly with open skies and there's no reason to cut back, " she said.

She said that recent negative news stories and comments about Shannon Airport's finances were fuelled by other aviation interests who were "jealous of our success".

A spokeswoman for the SAA said that it had no solid plans to scale back its nighttime retail operations. "We're simply reserving to do this if the demands of the business change, " she said.

She said that the SAA didn't propose reducing permanent staff numbers if it decided to close its retail operations at night. She admitted, however, that the downturn in military traffic presented the airport with difficulties.

"We've always said that open skies and the decline in military flights is a challenge for us but we have built up a good brand name in the US and we are the gateway to the west of Ireland."

Even with this week's deal with Omni Air, military traffic at Shannon Airport looks set to average around 20,000 troops per month this year, compared with its peak when almost 50,000 troops passed through the airport each month.

MILITARY MOVEMENTS THROUGH SHANNON (PASSENGERS) 2006 Jan 41,413 Feb 33,899 Mar 41,138 Apr 29,291 May 32,000 Jun 31,333 Jul 11,670 Aug 16,770 Sep 12,706 Oct 10,049 Nov 11,233 Dec 9,283 Total 280,785 2007 Jan 8,847 Feb 8,488 Mar 9,482 Apr - May - Jun - Jul - Aug - Sep - Oct - Nov - Dec - Total 26,817