Airport workers are threatening to walk out over tough new security checks.

Staff at Gatwick face the sack if they do not fill in a Disclosure Application Form, revealing past criminal convictions, by the end of the month.

Up to a quarter of the airport's 25,000-strong workforce have been told they must complete the form to qualify for airside passes.

They include catering staff, baggage handlers, security staff and bus drivers.

GMB union representative Frank Minal said many may have already quit over the measures.

He said: "There have been a lot of redundancies recently, at least 100 at the airport, and I wouldn't be surprised if many of them are to do with the checks.

"People are either worried about minor past convictions or are not prepared to go through more checks. We believe the introduction of the new regulations is Draconian.

"There is an understanding that some checks have to be made but this is about the way they are administered."

Gatwick bus driver Richard Symonds is among those thinking of quitting.

He said: "I have already been vetted and security-cleared at the very highest level by the MoD, GCHQ, MI5 and MI6.

"Now, in addition, I am required to complete a detailed form providing my birth certificate, passport, driving licence, National Insurance number and addresses lived at for the past ten years.

"I am very unwilling to co-operate with the new criminal record checks, not because I have anything to hide but because it is beyond doubt that security and intelligence gathering is being manipulated for political and ideological ends."

Mr Symonds, 50, from Ifield, Crawley, who is married with two children, has been told he will not be able to work on BAA property if he does not comply, despite being employed at the airport for more than 20 years.

In November, The Argus reported how baggage handler Michael Tomsett had his airside pass confiscated because he had been jailed more than 24 years ago.

Mr Tomsett, 46, of Setfolds Field, South Chailey, served eighteen months for arson in 1979.

He blamed his conviction on "getting mixed up with the wrong crowd."

His crime came under the category of "disqualifying offences."

Mr Minal said: "Someone may have committed a minor offence 15 years ago and that could exclude them from working.

"It is a sensitive area and certain information should be disclosed. But they are targeting the wrong people."

A Gatwick spokesman said he could not reveal how many people were affected by the measures.

He said: "We are well on the way to having all checks completed by July, a target set last June by the Government."

Ruth Carlyle, BAA Gatwick Airport Security Manager, said: "The Department for Transport (DfT) is responsible for setting security measures at all UK airports, which includes imposing the standards for the issuing of airside passes.

"BAA Gatwick is legally bound to meet these requirements.

"If an employee is found to have a conviction that matches an offence recognised by the DfT, then BAA is required to advise the employee's company and this includes suspending the pass while the matter is investigated fully."