Jack McConnell's job as Scottish Labour leader is under threat after it emerged three of his colleagues were being lined up as his successor.

MSPs Wendy Alexander,Margaret Curran and Andy Kerr are ready to replace McConnell if he resigns from his post. They are all waiting for the Motherwell and Wishaw MSP, who lost the Holyrood election to the SNP,to announce an exit strategy.

Labour MP Brian Donohoe has also entered the debate by saying that the home secretary,John Reid-who announced last week that he will leave his Cabinet post when Tony Blair quits office - should get McConnell's job.

The jockeying comes as senior Labour figures circle McConnell on the eve of a party summit in Edinburgh this week.

Several Labour figures told the Sunday Herald that they were waiting for McConnell to declare his intentions, by which they meant a departure date.

Of the three MSP contenders for the leadership,Alexander and Curran discussed their position with allies in the past few days.Alexander,whose botched bid for the top job in 2001 alienated sympathisers, called friends last week to talk about the future,while a source close to Curran said: "She's ruling nothing in and nothing out."

Curran's relations with McConnell were said to have worsened last week after the Labour leader stripped her of her role as the party's business manager.

She,like Kerr and Alexander, is understood to believe McConnell has a limited shelf-life as leader.But Kerr,a McConnell loyalist, has so far distanced himself from calls to replace his friend in the short-term.The Sunday Herald understands party figures want Kerr to tell McConnell his "time is up",an instruction the Labour leader would find difficult to ignore.

However, McConnell told his rivals yesterday that he intends to stay on as leader, despite losing to the SNP.

A source close to the first minister said: "There's no question of him resigning."

However, Labour insiders are concerned McConnell has not accepted his party's loss to the SNP, or even called Salmond to concede defeat. McConnell offered his congratulations to the SNP leader last week, but only in relation to Salmond being sworn in as an MSP.

Labour grievances are likely to be aired at an "away day" in Edinburgh this week, which has been pencilled in to take place after the parliament votes to install the nextfirstminister.WithSalmond expected to win the vote, McConnell could be put under pressure at the summit to outline his plans for the future.

Uncertainty about the Labour leader's position was given further credence by Ayrshire Central MP Donohoe, who said McConnell should be replaced by the home secretary, John Reid.

Donohoe, a Labour MP since 1992, said McConnell could stand down as MSP for Motherwell and Wishaw and make way for his Lanarkshire colleague.

"We should have a by-election in one of the MSP seats, and elect John into the Scottish parliament, and for him to become leader," he said.

The MP said the switch was being mulledoverbecauseReidwould "destroy" Salmond in the parliament.

"There is talk of it. It would sure fix the situation," he said.

However, it is unclear whether Reid is au fait with Donohoe's idea, and he issaid to be happy in London. Insiders say the rumours confirm the party is preparing for a post-McConnell era.

Kerr, Alexander and Curran could not be contacted last night.

An SNP spokesman said: "Now that it has dawned on the Labour Party in Scotland that they have lost this election, it seems they may also soon lose their leader."