Staff are angry at plans to close the final salary pension scheme to new employees and replace it with one that gives lower returns.

Amicus union said it hoped airport managers would reverse the plans.

Airport management have pledged to ensure passengers are not inconvenienced by the walkout.

We believe that closing the final salary scheme to new members will spell the end of their pension provision Peter Coulson, Amicus

In a ballot, 76% of ground and security staff and 100% of firefighters voted to strike.

Amicus said it will meet its representatives at Birmingham Airport on Monday to start planning strike action and warned it could close the airport over Christmas.

Peter Coulson, the union's regional officer, said: "This result demonstrates our members' determination to do everything possible to save their pensions.

"We believe that closing the final salary scheme to new members will spell the end of their pension provision."

Three ballots

In a statement, the airport said that some staff had recognised the measures it was proposing would put the pension scheme on a sound financial basis.

It went on: "In addition, approximately 80% of the scheme members have given their individual authority for the proposed changes to the scheme to help protect its long term future.

"Further proposals have been tabled by both sides and negotiations will continue next week.

"The airport company is committed to trying to find a solution acceptable to all parties and will do all it can to make sure that passengers are not inconvenienced."

The union has been negotiating with airport management on pensions for two years.

During that time Amicus members at the airport have rejected the pension proposals in three consultative ballots.