As per a union, reducing staffing numbers at the UK border force is leaving immigration officials at Dover and other ports with a difficult task.
A Kent representative of the Public and Commercial Services union, which represents border agency staff, said government funding cuts meant compromises were unavoidable.
Peter Norris said they had been handed a 25 percent cut in budgets over a four-year period.
As per a report in Kent Online Norris asserted "Our view is that is not possible without significantly restricting our ability to do the job. We are already cut to the bone and now the government wants us go even further."
His comments come as the cross-party Home Affairs select committee prepares to quiz Home Secretary Theresa May over the way in which border controls were relaxed.
Reports at the weekend suggested that four years ago, checks on passengers travelling on buses arriving at Dover were severely reduced after the authorities at Calais complained about congestion.
Carole Upshall, director of Border Force South and Europe, responsible for checks at Calais and the Eurostar terminal in Paris is among three senior managers to have been suspended in the wake of the disclosures.
Norris cautioned that managers were plugging gaps in immigration staff by transferring customs officers to do their job.
He added there was pressure on managers to exercise immigration control efficiently but if you have fewer people to do the job, there was a temptation to pull people from other areas.
He elaborated since the formation of the Border Agency, immigation and customs and excise staff have worked together under one organisation.