Charles Kennedy has called on the prime minister to clear up the future of the council tax.

Recent reports have suggested a forthcoming review will modify rather than overhaul the property based charge which many voters feel is unfair.

Kennedy challenged Tony Blair in the Commons on Wednesday to confirm he had "ruled out replacing the council tax as the principal source of taxation".

The Liberal Democrat leader wants to replace the levy with a local income tax and is calling on the government to do the same when it publishes its balance of funding review later this year.

He asked whether it was fair that "the poorest 10 per cent of the population pay four times as a much as a proportion of their income than the richest 10 per cent".

The prime minister said "there are problems with every system" of town hall taxation.

He said "nothing is ruled out [and] nothing is ruled in" during the review.

But Blair added that he did not believe it was right to "tax people by their income through the local authority".

"It is right that when he goes round the country promising to get rid of the council tax, as he does, that he explains to people that that would put at least 6p on income tax," he told Kennedy.