The leader of the Liberal Democrats in Liverpool has called on Deputy Prime Minister Nick Clegg to pull out of the coalition Government.
Warren Bradley, council leader until last year's election, said he was "tired of defending the indefensible" and urged Mr Clegg to act "before we disappear into the annals of history".
Mr Bradley warned the party leader that long-serving Lib Dem councillors were set to lose their seats in elections on May 5 "not because of their record, but because of your record and the perception of what we as Liberal Democrats now are".
In a private email to Mr Clegg, leaked to the Liverpool Echo, he said: "Unfortunately the boil is about to come to a head and burst (probably on election night) when we lose some very well respected and experienced colleagues from Liverpool City Council."
Mr Bradley said the Lib Dems needed to "reconsider what and who we are before we disappear into the annals of history as a political party who promised so much hope, yet failed because they wanted control and power".
The party had "deserted their followers", he said.
He told Mr Clegg: "I hope you take this in the spirit it is meant, liberal principles have to shine through, we have to be independent and we have to sever ties from the coalition; if we fail to do this, we have only our parliamentarians to blame."
But a Lib Dem spokesman said the letter "simply does not reflect the views of the wider Liberal Democrat membership".
He said: "Moving from a party of protest to a party of power has brought with it some very difficult decisions but we cannot hide from the fact the country is borrowing an extra £400 million every single day - the cost of a new primary school every 20 minutes."
He added: "Liberal Democrats are proud to be fighting, as always, on our strong record in local government and now for the first time in 65 years, on delivering in national government."
