Jack McConnell will sign the agreement

The agreement could be a significant step in improving relations between the executive and the unions.

Tensions have arisen over some UK Government policies, with public, private partnerships a particular bone of contention.

On Monday, First Minister Jack McConnell will sign a memorandum of understanding with the Scottish TUC at its conference in Perth.

That will commit ministers and civil servants to involving the unions more closely and systematically in policy preparation.

In return, the unions will guarantee to respond promptly to executive initiatives.

There has been no formal comment ahead of Monday's deal - but senior union sources said this approach contrasts markedly with what they regard as anti-union rhetoric heard from some ministers in the UK Government.

They stress, however, that they want to see how the deal works in practice.