Three more days of nationwide postal strikes at Royal Mail in Britain began on Thursday.
A total of 43,700 union members in mail centres, delivery units in mail centres, network logistic drivers and garage staff are on a 24-hour strike.
Further 24-hour strikes are due to take place on Friday and Saturday.
Royal Mail management and Communication Workers Union bosses have been meeting all week, but each is blaming the other for the lack of agreement.
The BBC reports this week's strikes follow two 24-hour stoppages last week.
Royal Mail said on Wednesday it expected its backlog to have fallen from 30 million to two million items by the end of the day.
It says almost all of these letters and parcels were awaiting delivery in London.
The CWU says the backlog was in excess of 100 million items at its peak.