Ministers are considering deploying troops to secure Britain’s borders during the planned strike by immigration officers and other public sector workers on Wednesday.
Francis Maude, Cabinet Office minister, on Sunday refused to rule out using military personnel at immigration checkpoints at airports and ports when officials from the UK Border Agency join the industrial action.
Heathrow airport fears paralysis because of the strike, and BAA, its owner, will on Monday assess whether it has persuaded airlines to halve the number of passengers they bring into London on Wednesday.
Mr Maude signalled the government would if necessary use troops to secure borders and minimise disruption for travellers.
“If that’s what is needed – it’s not what we’d prefer to do – but if that is needed, I am told the UK Border Agency are looking at all the options,” he told Sky.
BAA is warning it could take 12 hours for travellers to clear passport checkpoints at Heathrow next Wednesday because of the strike, and is concerned about gridlock at the airport unless domestic and foreign airlines drastically reduce the number of international passengers coming to the UK.
Heathrow could grind to a halt if people on arriving aircraft have to be kept on board for long periods because of big queues at passport controls.
Such a scenario could in turn make it impossible for departing aircraft to take on passengers and fly out of Heathrow.
“We have received positive responses so far from airlines about their willingness to reduce the number of arriving passengers at Heathrow, and we will be in a better position on Monday to understand whether the reductions that have been made will be sufficient to avoid cancellations of departing aircraft,” said BAA.
If BAA concludes that airlines are still planning to bring in too many passengers on Wednesday, it will consider other options, including the possibility of reducing the number of flights into Heathrow.
Sir Gus O’Donnell, cabinet secretary, wrote to permanent secretaries at other Whitehall departments on Friday, asking for civil servants to volunteer to work on immigration checkpoints.
BAA is assuming that staffing levels at passport control will be at least 50 per cent below normal levels.
Moreover, even if staffing is at 50 per cent, travellers coming from destinations outside the European Union are likely to face long delays because the temporary staff on passport controls will not be familiar with the more stringent checks made on non-EU citizens.
The UK Border Agency said: “Securing the border is our priority and over the last weeks and months we have considered all options to ensure we are prepared for union action.”