However TUC sources understand that the idea was floated by a senior party figure at a dinner with political correspondents at the annual congress in Blackpool.
Mr Blair's office denied there was any such proposal: "There is no foundation in the story and there is no such proposal."
However the supposed strategy was revealed after a week in which the party came under constant fire from the unions at the TUC conference. Union leaders are known to have warned Mr Blair of industrial unrest two to three years into a Labour government.
Union leaders privately registered a combination of scepticism and fury last night, saying that such a proposal would have to face a vote at the Labour conference, which makes policy and where unions still command half of the vote.
If such a referendum among party members was held, however, and it went in favour of a divorce between the two wings of the Labour movement, there would be strong pressure on the party conference to rubber-stamp the decision.
Another interpretation was that senior party figures are "simply playing politics" after a week in which they came under constant fire from the officiates.
Unions established the party in the early 20th century and have continued to be its main financial backers ever since.
Stephen Byers, Labour's employment spokesman, said last night: "There is no basis for running these kinds of stories based on any comments I might have made."
The stories originated at a dinner on Wednesday night attended by journalists from four national papers who this morning report that the Labour leadership has plans completely to distance the party from the trade unions if strikes make a Labour government unpopular.
"It is a ludicrous proposition," said Mr Byers.
A senior union official said: "It is not within the gift of the Labour leader to cut the union link. Any such proposal would be a matter for the party and the unions as a whole. This is not on the agenda."
It seems however that key policy spokesmen are being used to float ideas which the leader's office can subsequently deny. Another union official said: "They are flying kites."Reuse content