BRITISH Airways cabin crew leaders called on the Government today to launch an urgent investigation into the "rushing through" of 1,000 volunteer staff to help break this weekend’s strike.

Unite wrote to Transport Secretary Lord Adonis warning that the use of "fast-tracked, under-trained volunteers" risked hitting the reputation of the company and of the country for high safety standards in the transport industry.

The union said: "Given recent developments, Unite is writing formally to you to request an urgent investigation by your department into the rushing through of stand-in cabin crew and ask that you take all steps to assure yourself, the Government and the travelling public that during this dispute corners have not been cut in the standards which govern our aviation industry."

Unite voiced a number of concerns over the use of volunteers to stand in for thousands of cabin crew who are set to launch a three-day strike from Saturday in a bitter row over cost-cutting.

The union questioned the compliance of the volunteers with UK security checks as well as BA’s duty to other governments to comply with their vetting laws.

The development came amid fading hopes of a last-minute deal to avert the strikes and a further four-day walk-out from March 27.

BA insisted that all the volunteers are fully trained and safety would never be compromised.

Union sources later disputed BA's claim to have 1,000 volunteers ready to work this weekend, alleging that only 345 workers had been trained.

BA strongly denied the claim.