By Ian Dunt Follow @IanDunt
Queues at Britain's ports could last for 12 hours on the day of the public sector strike, according to reports.
Next week's strike, which could see over two million people down tools, is expected to see some of its worst repercussions at airports, where ministers are trying to train civil servants to take on the role of UK Border Agency (UKBA) staff.
Officials warned Heathrow could "grind to a halt", with those coming off planes waiting up to 12 hours at immigration.
Some reports suggest the incoming crisis is a direct result of the border scandal which threatened to engulf Theresa May earlier this month.
According to the Guardian, a number of trained middle management figures at UKBA are walking out due to the way their seniors were treated during the row, when UK Border Force head Brodie Clarke was forced to resign after a string of public attacks by the home secretary.
With the memory of that encounter still fresh in the memory, Ms May is understood to be resisting any efforts to limit security checks on incoming passengers next Wednesday.
That leaves both aspects of the Home Office's contingency arrangements – alternate staff and reduced checks – in pieces, signalling a day of chaos at Britain's borders.
Rhetoric around the strike escalated dramatically yesterday, when Danny Alexander and Francis Maude, lead government negotiators over public sector pensions, claimed the action would cost £500 million and lead to many job losses.
Pressed on the details of the statement, the ministers admitted they could not put a figure on claimed job losses and that the revenue impact of the strike would be no greater than that of a normal public holiday, such as the Queen's birthday.
"There is no question the strikes will have an impact. It is not costless, if lots of people can't go to work because they have to look after kids, that has an impact on output. That is a fact," the prime minister's spokesman said
TUC general secretary Brendan Barber accused the government of "fantasy economics" and said it was seeking excuses for what is expected to be a depressing autumn statement next week.
“This is the clearest sign yet that next week’s autumn statement will be a damp squib and the government is using the strike as yet another desperate excuse," he said.
“Blaming the weather, the royal wedding and now scapegoating hard-working teachers, nurses and dinner ladies for the UK’s economic woes is pretty poor from a government that has presided over record unemployment and the weakest economic recovery for a century.
“Dedicated public sector workers take no pleasure in taking action next week but the blame for this strike lies squarely with the government for failing to engage in serious talks until unions decided on a day of action.”
UCU general secretary Sally Hunt said: “So far this week the government has blamed everything but the weather on the wicked trade unions. If it starts raining though, expect to see Brendan Barber put in the frame for that too.
“We are far from the reds under the beds portrayed by government. We are public servants who want to be at work supporting the next generation rather than on the picket line. Instead of continuing his desperate search to find someone to blame for the impending strike on November 30th, the prime minister should stop, pause and look in the mirror."
Prime minister David Cameron hit back: "Everyone should be clear there is going to be disruption and the reason for that disruption, the responsibility for that disruption, lies squarely with the trade union leaders who've decided on a strike even while negotiations are on-going.
"I think that is irresponsible, I think it is wrong and people should know who to blame."