Gordon Brown flagged up Middle East peace and economic prosperity in Palestine as key planks of his foreign policy yesterday as he continued his charm offensive on the British electorate.

Mr Brown, on course to succeeding Tony Blair as Prime Minister on June 27, repeated his belief that it was necessary to have an economic building block for the peace plan.

Speaking at an arts festival in Brighton as part of a plan to reveal more of himself to the British people, he said: "Just as in Northern Ireland people realised they could have prosperity and peace and that a return to violence means a loss of peace and a loss of prosperity, we have got to build a peace to give prosperity to Palestinians."

Acknowledging the country was deeply divided over Iraq, he told the 1500-strong audience, each of whom had paid £10 to hear him speak, that it was also necessary to look beyond military insecurity and allow residents of Iraq and Afghanistan to feel they had a stake in their countries.

Mr Brown intends to visit Iraq and the Middle East within weeks to discuss the future with the politicians and military personnel on the ground but yesterday remained confident that British troops would be withdrawing from the war-torn country.

Speaking to Anthony Minghella in the Dome Concert Hall, he said: "There will be less troops in Iraq next month and the month after."

In an earlier interview with Andrew Marr on the BBC, the Chancellor set out his vision for a home-owning, asset-owning, wealth-owning democracy.

In the first policy announcement of his leadership campaign, he revealed plans to build five new eco towns with up to 100,000 low carbon or carbon neutral homes which will be powered by locally-generated energy from sustainable sources.

The Tories, who believe they have made the political running on the environment, mocked Mr Brown's commitment. George Osborne, Shadow Chancellor, said: "It's another example of same old Labour, same old spin."

On the NHS, Mr Brown ruled out the possibility of making the NHS independent but there is no doubt he intends to change aspects of its management.

Appalled that the government's reputation has suffered over its handling of the NHS despite record investment he signalled his intention to make NHS provision a top priority.

Labour's national executive agreed yesterday, in a move to boost membership, that anyone who joined the Labour party before June 1 could take part in the election for the leader and deputy leader. Ballots will close on June 22 and the result will be announced on June 24 at a specially-convened meeting in Manchester.

At that point Mr Blair ceases to be leader of the Labour Party but he will not hand over the seal of prime ministerial office until he meets the Queen in Buckingham Palace on June 27.

Mr Brown is the only credible successor to Tony Blair. However, Michael Meacher and John McDonnell, two self-styled Labour left wingers, are contemplating the possibility of a challenge, if only they could agree on who has the best chance of getting the most nominations.

Each contender for the leadership and the deputy leadership will need the backing of 45 MPs. The nominations will open at 2.30 pm today.

They will be posted on the website tomorrow and will be updated twice daily to show who is set to be on the ballot paper. Nominations will close on Thursday and the successful candidates will be entered on the ballot paper which will be distributed to the electoral college. Party members, unions and MPs and MEPs, each have a third of the vote.