Charles Kennedy has pledged his party's support for efforts to boost free trade.

In a keynote speech on Thursday, the Liberal Democrat leader was set to say that economic liberalism is one of his party's core beliefs.

Kennedy sought to allay as "largely unfounded" any fears about globalisation among the party's grassroots supporters.

"The evidence and experience suggests that poor people in poor countries benefit from open economies. But there are understandable concerns stemming from the injustices and inequalities in the world.

"In any event, globalisation will not go away. Globalisation can act as a force for good in the world - and particularly in the developing world," he was expected to say.

Kennedy argues that the increasing importance businesses place on corporate social responsibility shows "pure untrammelled free market capitalism has lost its appeal".

"The frontiers of privatisation have been pushed to their limits - maybe beyond them. But there is no serious case being argued for nationalisation of the commanding heights of the economy," he was to say.

Ahead of his party's annual spring conference, Kennedy gave the second in a series of speeches on the Liberal Democrat ideals that underpin the policies that will form the next general election manifesto.

The speech, entitled "Reclaiming Adam Smith", was to take place at the London headquarters of Bloomberg in a bid to show that the party has business-friendly credentials.

He backed less protectionism and for the World Trade Organisation to be given more powers.

"A body like the World Trade Organisation can be a force for good. It is ironical that the WTO faces almost equal attack from the left and from the right. The right dislikes the fact that it encroaches on national sovereignty. The left feels that it is promoting global capitalism. Liberal Democrats should refute both charges."

"The problem with the WTO is not that it has too much power. It is that it has too little."

He will say that the man credited as the champion of free market thinking should not be seen as a darling of the right.

"Although Adam Smith has been lionised by Lady Thatcher's acolytes, he was one of the earliest advocates of tax-financed public education."

The Lib Dem leader also sought less regulation and a simpler, more transparent tax system, promising that the party will not back "taxation for taxation's sake".

"We do not, as it happens, at the moment believe that it is necessary to increase taxation. There are in fact people on low incomes who should be paying lower tax or no tax at all."

He also refuted the image portrayed by political rivals that the party believes "profit is a dirty word".

"In a liberal society, people should be free to earn what they can in any lawful way that they can. We do not practise the politics of envy."