A band of political sisters have joined the Robin Hood Tax campaign.

Labour's Lucy Powell - candidate for Withington - along with North West MEP Arlene McCarthy and Baroness Glenys Kinnock, made a symbolic change from their usual red party colour to green to show their support.

The campaign for a Robin Hood Tax wants a tax of half a per cent to be levied on bankers to tackle poverty and climate change, both in the UK and abroad.

Campaigners say the tax would raise billions of pounds, and the idea has attracted a huge internet campaign in just a few weeks.

Lucy Powell said: "This is an initiative that the public want action on and is already backed by many people in Withington.

"This tiny tax on some banking transactions could provide crucial additional funds for local public services, saving lives and also helping to reduce global poverty."

MEP and vice chair of the economic and monetary affairs committee, Arlene McCarthy, said: "The European Parliament voted overwhelmingly to back a financial transaction tax. The time has come for radical action to ensure the financial sector pays its way in the wake of the crisis.

"There is now a growing momentum for a global levy on banks' activities to tackle speculators and to support climate change and developing countries."

And Baroness Glenys Kinnock said: "A 0.05% tax on financial transactions could generate £250 billion to help developing countries who have been hit hardest by the financial crisis. None-government organisations including Oxfam and ActionAid are showing their support, and as a government we want to take this momentum forward."

Prime Minister Gordon Brown, German Chancellor Angela Merkel and French President Nicolas Sarkozy have all spoken out in support of a tax on financial transactions.