A PCS Union spokesman said:
The issues of the last few days has brought to the public's attention what we have said for a long time, that ministers can't cut staff and expect to run the same service - not just on passport controls at Heathrow, but right across UKBA.
Clearly, the cuts already made have had a major impact and further cuts planned every year until 2015 will make the situation even worse.
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A lamp in the tower which houses Big Ben is to be switched off for the first time in more than 70 years.
Sir Bruce entertained audiences for more than seven decades.
Work in the tower will also pause over the bank holiday weekend.