Scores of postmen and women in Oxford are set to discuss possible strike action in a row over workload.

Postal workers said they were concerned about increases to the area of their delivery rounds in the city - and warned mail was being delivered later as a result.

Dozens of postal delivery workers are expected to attend a meeting, organised by the Communication Workers' Union (CWU), on Sunday to discuss whether to ballot for industrial action.

If they decide to hold a ballot - and workers vote in favour of a strike - up to 300 postmen and women across the city could end up walking out.

CWU area delivery representative Kevin Duffy said Royal Mail implemented the changes to workers' rounds two weeks ago.

Mr Duffy said all areas of Oxford were affected and some letters were being delivered later than the national deadline of 2pm for urban areas, sometimes as late as 3pm.

He said: "Basically they are making the postmen take on extra work with no agreement with the union and the quality to the customer because of that is getting worse."

Mr Duffy, who has been a postman in Headington for 28 years, said they were being given extra streets to deliver to after they finished their regular rounds.

Mr Duffy said other branches of the CWU were considering holding meetings to discuss the same issues in towns such as Abingdon and Bicester.

He said: "It's bad, but it's going to get worse. It's at breaking point at the moment."

Last June, 2,000 county postal workers went on strike as part of a national dispute. A month later the suspension of two workers at Cowley sparked a six-day wildcat strike.

And last month, Royal Mail staff warned they could strike again in a bid to prevent the Oxford Mail Centre closing when the company shifts its operation to Swindon, expected to be completed next summer.

A Royal Mail spokesman said: "Changing duties to match workloads during the summer period was included in the national agreement with the CWU following last year's strikes. This will not prevent Royal Mail from meeting our delivery specifications."

Sunday's meeting is due to be held at Cowley Workers' Club, in Between Towns Road, at 10.30am.