In his closing conference speech - set to be dominated by international events - Lib Dem leader Charles Kennedy will tell the party faithful they must remain united if they are to take their fight to Iain Duncan Smith's Conservatives and become an "effective opposition".

"That message will be absolutely vital as we develop our role as the effective opposition but that message alone must not be enough. Our challenge is to be more competent, more authoritative, more engaging and quicker on our feet than either of the other parties," he will say.

Kennedy will also warn the Lib Dems that the interests of public service unions should not take precedence over the needs of those they serve.

"Our principle is that public service professionals should have the freedom to deliver high-quality public services, not in the interests of the producers but in the interests of the community," he is expected to say.