The passport office at Peterborough could be one of those affected if unions go ahead with threatened industrial action over job cuts.

The Public and Commercial Services union claims it is job cuts that have caused the current passport backlogs.

A letter landing on Passport Office chief executive Paul Pugh’s desk this morning states the union attributes the current crisis to “major job cuts and office closures during the past five years”, as well as the increasing use of private companies.

It comes as the union is preparing to hold a consultative ballot of all its quarter of a million civil and public service members with a view to taking part in joint union action over pay, starting with a one-day strike in July.

The passports letter points out 22 interview offices and one application processing centre have closed in recent years and 315 staff, one tenth of the workforce, has lost their jobs. It also notes staff is battling a backlog of almost half a million cases.

The union says its warnings about the damage cuts would do have been ignored and blames senior officials for a “lack of forward thinking”, adding: “We do not accept that the current problems can solely be down to unusual demand.”

The union also complains it was not consulted on the redeployment of workers to clear the backlogs, including 25% of the staff who work on fraud prevention and investigation.

The letter from the union’s Home Office group secretary Mike Jones calls for urgent negotiations to identify “where additional permanent jobs are needed with a firm assurance that these jobs will be filled as soon as possible”, as well as talks to address low pay in the passport office and the latest privatisation threat.

It ends: “If we do not get a satisfactory response by 30 June 2014 we will be considering industrial action.”

PCS general secretary Mark Serwotka said: “The passport office is failing holidaymakers because of a political decision to cut staff and close local offices.

“While the economy is showing signs of recovery for some, the damage being done by the government’s spending cuts is evident to anyone trying to get a passport at the moment and we are not prepared to stand by and allow this to happen.”