Holidaymakers are facing an anxious wait to see if their travel plans will be ruined after a vote for strike action by BAA staff. The airport operator face "a total shutdown" at Heathrow, Stansted, Southampton, Glasgow, Edinburgh and Aberdeen after a strike ballot by members of the Unite union. The earliest a strike could be called would be Monday August 23 - just ahead of the bank holiday weekend. But hopes of a compromise remain. The union has said that no decision over the form or date of any strike will be taken before Monday. Conciliation service Acas said it was arranging an early meeting between the two sides. Upset over what they describe as a "measly" pay offer from BAA, union leaders said there was still time for BAA to "get round the table and negotiate" and that it would "not take much" to sort out the dispute. The union, which is already embroiled in a row over pay and conditions with airline BA, is facing criticism over the news of more potential walkouts. Before the ballot was announced, Prime Minister David Cameron said a strike would "do nothing but harm" and would damage business, jobs and tourism. Daniel de Carvalho, a spokesman for budget airline Ryanair, said: "There is no justification for any strikes by these selfish and underworked Unite members at a time when traffic at BAA's airports is falling and they are even less busy than they were last year."