Patricia Hewitt, Health Secretary, appeared not to know who Scotland's First Minister was yesterday, marring a Labour event intended to show how Westminster and Holyrood were working together.

On STV, she extolled the virtues of the smoking ban in Scotland but came unstuck when she repeatedly referred to the First Minister as "Jack McDonald".

She said: "People are worried about possible loss of trade but what Jack McDonald was telling me was" She continued: "And one of the most reassuring things I've just heard from Jack McDonald"

The interviewer pointed out her gaffe, saying: "Jack McConnell." Ms Hewitt frowned: "What did I say?" The interviewer replied: "McDonald, I think."

Ms Hewitt declared: "Oh God, I'm sorry." She laughed. "Why don't we just do that one again?"

An embarrassed Labour aide eased a hand over the lens.

Angus Robertson, SNP campaign chief, branded Mr McConnell "the invisible man of Scottish politics". He said: "The fact ministers in London don't even know (his) name makes a mockery of his partnership claims."