A decision on whether to press ahead with a fresh wave of postal strikes will be taken by union leaders just hours before the industrial action is set to start.
The postal executive of the Communication Workers Union will meet to discuss any progress made during talks with the Royal Mail aimed at breaking a deadlocked row over jobs, pay and modernisation.
The two sides have been locked in negotiations after agreeing to meet under the chairmanship of TUC general secretary Brendan Barber.
The union's postal executive was briefed by CWU negotiators on Tuesday, while Royal Mail chief executive Adam Crozier was given details of the talks by managing director Mark Higson who is leading the management team.
Up to 120,000 CWU members staged two 24-hour walkouts last week, which delayed more than 30 million items of mail.
A similar number of workers are due to strike on Thursday, Friday and Saturday, threatening fresh disruption to deliveries.
The union has announced that: 43,700 staff in mail centres, as well as drivers and garage staff, will strike on Thursday; 400 workers in Plymouth, Stockport and Stoke dealing with badly addressed mail will strike on Friday; and 77,000 delivery and collection staff will walk out on Saturday.
Mr Barber described the talks as "useful," adding that further work was being done to try to reach an agreement.
The TUC leader was involved in drawing up a deal which ended the last national post strike two years ago.
