Although a number of male Cabinet members have also been fingered, attacks on these four have often been of a particularly personal nature.
The revelation comes after comments by Clare Short, the International Development Secretary, to a documentary crew that another member of the Cabinet had lied to a newspaper over remarks she made about parades in Northern Ireland. On the same day there were renewed rumours that Harriet Harman, the Social Security Secretary, was about to be sacked because other ministers have lost confidence in her.
The Northern Ireland Secretary, Mo Mowlam, faced whispered claims, apparently from figures in the Unionist camp, that she was not up to her job because of her illness last year. And last week Conservatives were saying they had learned Margaret Beckett might be moved from the Department of Trade and Industry because she was felt to be incompetent.
Such rumours are part of the currency of Westminster life, and male ministers including Gavin Strang, the Transport Minister, and David Clark, the Chancellor of the Duchy of Lancaster, have also had to cope with them.
But friends of the women in the Cabinet suggested some of them were targeted because of their more "human" political styles. One such source said: "Women tend to deal with more human issues and they speak in a far more personal way, whereas men deal in theories and practical types of issues. That can leave women open to greater criticism, because they are dealing with emotions quite often. "Women are often criticised for things men are never criticised for, the way they look or their relationships." A friend of Clare Short said she had been congratulated by some of her colleagues for her outspoken response to these campaigns, which had dogged her since long before she joined the Cabinet.
"If she's being undermined she won't sit there and take it. People know they may well get fingered if they have a go at her." Yesterday a Downing Street spokesman defended Ms Harman after two newspapers suggested she was about to be sacked. "The person who knows when there might be a reshuffle is the Prime Minister.
"The Prime Minister believes Harriet Harman is doing a difficult job and doing it well, and he has said that on occasion," he said. Such stories tended to pop up on quiet news days, he added.
Yesterday's Daily Express pointed to tension between Tony Blair and Gordon Brown as a possible reason some of last week's rumours.
Ms Harman was appointed on Mr Brown's advice, it said, and Mrs Beckett was also seen as an ally of the Chancellor.
While Ms Short's outspoken nature often makes her a target, attacks on Ms Mowlam are more likely to be a result of the tightrope she is forced to walk to keep the Northern Ireland peace talks together.
She has been the subject of bitter attacks by Unionists, and there have been tales circulating that she might be given an alternative role in co-ordinating the party message.
However, these stories have been denied by government sources who have said her work in Northern Ireland has been too important and too successful for her to be moved.
Mr Clark and Mr Strang have both been mooted as possible casualties in a summer reshuffle. Mr Clark has complained publicly about smears, though Mr Strang has remained silent.Reuse content