SOUTHAMPTON workers employed by the UK’s largest mobile crane hire firm are taking part in a national strike over pay.

Crane operators working for Ainscough staged a picket outside the Southampton branch of the company in a move that could hit construction sites across the south.

About 30 staff at the Ainscough depot on the Millbrook trading estate are taking part in the nationwide walk-out. The company’s 500 crane operators have rejected a revised offer that comprises a 2.5-per-cent pay increase this year followed by a 2.75-per-cent rise in 2017.

A series of strikes and overtime bans are due to take place at the company’s 30 depots between now and March 23.

The crane operators are members of the Unite union, which has described the pay offer as"derisory".

Bernard McAulay, Unite's national officer for construction, said: “Our members are highly skilled crane operatives working on some of the UK’s premier construction sites in challenging conditions. They deserve better from their multi-million profit-making employer.

“Our members’ hard work, skills and dedication have helped make Ainscough the highly profitable and respected business it is today.

"They are justifiably angry that the company can boast of making a £14 million profit last year and yet offer a derisory pay increase in return.

“Ainscough needs to heed this warning and come back to the negotiating table with an improved pay offer or risk major disruption to its UK-wide operations."

Unite has accused Ainscough of trying to impose zero hours contracts - a claim the company denies.

A company spokesman said the pay deal comprised a 2.5-per-cent increase in base rate, plus a new 1.5-per-cent depot performance bonus and an enhanced mileage rate.

He said this would be followed by a further 2.75-per-cent increase in base rate and a rise in the performance bonus.

The spokesman added that proposed changes to the holiday pay formula represented average increases of 2.1-per-cent in the first year and 2.3-per-cent in the second year.