Deputy Labour Party leader Harriet Harman has apologised after calling treasury minister Danny Alexander a "ginger rodent".
Ms Harman used her speech to Labour's Scottish conference in Oban to launch a fierce attack on the Liberal Democrats in government, including Mr Alexander and Scottish Secretary Michael Moore.
She said: "Many of us in the Labour Party are conservationists, and we all love the red squirrel.
"But there's one ginger rodent we never want to see in the highlands of Scotland - Danny Alexander."
Ms Harman's speech was intended to support Scottish Labour leader Iain Gray in his bid to replace Alex Salmond as First Minister at Holyrood in next May's Scottish elections.
But she was forced to issue an apology after her remarks about Mr Alexander, who is MP for Inverness, Nairn, Badenoch and Strathspey as well as Chief Secretary to the Treasury, were condemned as "personal abuse" and "anti-Scottish".
Mrs Harman admitted she had been "wrong" to use the description about the Liberal Democrat Chief Treasury Secretary Danny Alexander.
A statement issued by Labour said: "Harriet Harman has today apologised for her comment about Danny Alexander and says it was wrong."
Nationalist MSP Shirley-Anne Somerville, herself a redhead, said Ms Harman's "silly remark isn't anti-Danny or anti-Lib Dem: it's anti-Scottish."
"It's a gaffe that is overshadowing what Iain Gray thinks should be his big day," the Lothians MSP added.
"There's a mountain of issues people can criticise Danny Alexander for but childish abuse about his appearance reveals Labour have little to say about the real issues of Westminster cuts."
Ms Harman also urged Labour Party members to make First Minister Alex Salmond and his deputy Nicola Sturgeon an "endangered species" by ousting them from Holyrood next May.
She said: "We are here in the west coast of Scotland, where there is a long-standing fishing community, and we are second to none in our support for the fishing industry.
"But by next May we want Salmon and Sturgeon to be an endangered species."
She also branded Scottish Secretary Michael Moore, who is Liberal Democrat MP for Berwickshire, Roxburgh and Selkirk, the "invisible man" of Westminster.
The Liberal Democrats dismissed Ms Harman's remarks as "personal abuse".
George Lyon, Scottish Lib Dem election chair, said: "There is no depths to which the Labour Party will not stoop.
"They aren't fit to be in opposition, let alone in government.
"Instead of throwing personal abuse at the Liberal Democrats, Harriet Harman should be apologising for the shocking financial mess her government created."