Wildcat industrial action began at Oxford's main sorting office in Cowley on Tuesday night. The dispute is over a number of claims of bullying.

Talks between unions and Royal Mail bosses continued on Saturday, with the list of proposals being drawn up.

Royal Mail says it is taking the claims seriously and an inquiry is under way.

A spokesman for the company described Saturday's talks as constructive and positive.

Hundreds of thousands of letters have been caught in the backlog since the strike began.

The centre was also hit by a series of wildcat strikes last year.