Senior Tories have held secret talks with trade union leaders to pave the way for a highly symbolic meeting between David Cameron and the TUC general secretary Brendan Barber.
Despite the threat of industrial strife over the Government's planned spending cuts, both sides believe Mr Barber is likely to be welcomed into Downing Street in the autumn.
Relations between union leaders and Conservative prime ministers were positively glacial during the 1980s and 1990s.
But senior Tories are increasingly hopeful that they may have achieved at least a mild thaw. Both sides privately report a willingness to do business with each other.
Tory sources said the party had been successfully “building bridges” with senior trade unionists in recent months and pointed out that several ministers have either met trade union leaders or addressed TUC events.
They said they were “highly optimistic” that a meeting could be arranged between the Prime Minister and Mr Barber towards the end of the year.