A credit-crunch war appears to have broken out with all three main parties hinting at cutting taxes to win votes. In his annual address to the City of London, Prime Minister Gordon Brown urged action to get the economy moving. He gave a broad hint that plans to cut taxes were being drawn up although reports that the reductions could total up to £15 billion have been downplayed. But full details of what the Government is proposing will have to wait until Chancellor Alistair Darling publishes his Pre-Budget Report some time over the next few weeks. Opposition leader David Cameron will set out details of the Tories' promised tax cut later. It is thought that the Conservative leader will propose a reduction in national employers' insurance contributions for small firms that retain or take on new staff. And Liberal Democrat leader Nick Clegg will warn that the world can only dig its way out of recession through international co-operation. In a speech to the Royal Commonwealth Society, he will welcome the opportunity for wider co-operation offered by the election of Barack Obama as the next president of the United States. He will echo Gordon Brown in calling for far-reaching reform of the main international institutions including the International Monetary Fund, the World Bank and the United Nations.