Members of the Civil and Public Services Association, which claims to represent about 2,000 of the 3,500 front-line customs staff, are being balloted on a one-day stoppage over new shift arrangements which the union says will result in a loss of earnings. Staff are also objecting to proposals to make Sunday shift working compulsory. The result of the ballot will be known at the end of the month.
The changes have led to job losses at airports and ports. Under the new rules red and green entry channels have been abolished and commercial freight traffic from the EC is no longer to be checked on entry to Britain.
About 400 staff have been relocated from ports handling large volumes of European trade to other jobs within Customs and Excise.
The port checks are to be replaced by an intelligence system to combat activities such as drug smuggling.
Goods imported from outside the EC will not be affected by the changes.
A spokesman for Customs and Excise said that negotiations on shift patterns and overtime were being conducted at local level.