Crucial talks on strikes at Royal Mail hosted by the Trades Union Congress (TUC) did not reach agreement but will continue tomorrow.
Brendan Barber, the general secretary of the TUC, delivered a brief statement to journalists waiting outside Congress House after seven hours of negotiations.
"We've had useful talks but we're now going to adjourn overnight to allow some work to be done on some of the issues involved. But we'll be reconvening again to continue the talks tomorrow morning," Mr Barber said.
"In the meantime, both the Royal Mail and the CWU have agreed to make no further comment."
The Communication Workers' Union (CWU), having led postal workers through two days of strikes last week, is set to strike on Thursday, Friday and Saturday unless agreement is reached this week.
Its clash with Royal Mail, which insists it must carry out a modernisation programme to make it profitable in the internet age, has so far failed to reach an impasse. CWU chiefs have blamed the government, which opposes a strike, for not intervening.
Deputy general secretary Dave Ward reiterated attacks against business secretary Peter Mandelson this morning, telling journalists: "He's not telling the truth about what the dispute's about."
Mr Ward made clear Royal Mail's pensions deficit was a fundamental sticking point which required resolution.
"What I'd say to Peter Mandelson is: you can't keep on sitting on the sidelines," he added.
"Unless we find a solution to the pension deficit very quickly this company has no prospect of building a successful future."