The drugs were found by Apache Corp. staff, bound for a worker on a platform on the Forties field, east of Aberdeen. The field was recently sold by Shell to Apache.

Medical staff carrying out the tests were sent to the platform unannounced after the find.

While a union spokesman said this was a slight on the integrity of the workers by an 'employer who's only just got their feet under the table', Apache defended its actions.

An Apache spokesman is reported to have said that while he accepted no drug culture existed offshore, it would have been wrong not to take action.

He said police had determined the package contained amphetamines and Apache then decided it was a safety issue.

In the interests of not jeopardising the safety of anyone offshore, he said Apache screened around 350 people.