Lib Dem leader Nick Clegg will open his party's Scottish conference in Perth with a pledge to clean up politics.
Liberal Democrat leader Nick Clegg has pledged to clean up politics in the wake of the MP expenses scandal and concern over party donations.
He will also spotlight key manifesto themes for the forthcoming election campaign, saying his party stands for fairness and a good start for children.
He told the Scottish Lib Dem conference the Westminster parliament was looked on with "disgust", rather than pride.
Mr Clegg has delayed his speech to avoid clashing with Gordon Brown's appearance at the Chilcot inquiry into the Iraq war.
Mr Clegg also set out his vision for a "fairer" society, through tax reform and a better start for children.
Scottish Lib Dem leader Tavish Scott will address delegates on Saturday.
And he attacked Gordon Brown for backing the Iraq War in his evidence to the Chilcot inquiry.
Meanwhile, a senior member of the party has all but ruled out a power-sharing deal with Gordon Brown in the event of a hung parliament at Westminster after the election.
The Liberal Democrats have declared themselves as the main challengers to Labour in Scotland in the forthcoming general election.
'Direct challengers'
Amid talk of a possible hung parliament at Westminster, a senior Lib Dem all but ruled out a power-sharing deal with Gordon Brown in the event of a hung parliament at Westminster after the election.
In a BBC Scotland interview at the conference, Liberal Democrat Scottish affairs spokesman Alistair Carmichael said he could not imagine the circumstances in which his party would prop up a minority Labour government.
In a BBC Scotland interview at the Perth conference, Liberal Democrat Scottish affairs spokesman Alistair Carmichael said he could not imagine the circumstances in which his party would prop up a minority Labour government.
In Scotland, the party is positioning itself as direct challengers to Labour in the forthcoming UK election in seats across Aberdeen, Edinburgh and Glasgow, where the Liberal Democrats are already represented in the Scottish Parliament.
Mr Clegg will tell delegates that Labour has failed to deliver for Scotland.
He will say: "Labour's banking crisis and recession has caused serious damage to the Scottish economy and businesses.
"Under the Labour government the gap between rich and poor has grown wider and social mobility has foundered.
"In Scotland, life expectancy remains lower than anywhere else in the UK and it is losing jobs at the fastest rate in Western Europe."
The Lib Dem leader will claim that his party is the only one which can deliver change and pledge to free half a million Scots on low incomes from having to pay any income tax.
