Speaking on the final day of the G8 summit in Japan, the Prime Minister said the leaders gathered there had been united in their disgust at the violence being meted out in Zimbabwe against the opposition.

He said the package of proposed sanctions agreed on Tuesday night by the G8 leaders included targeted measures against 14 named individuals associated with the regime as well as an arms embargo.

"The mood is outrage against what is happening in Zimbabwe, disgust at the behaviour of the Zimbabwe regime, an acceptance by all of them that this is an illegitimate regime that has got blood on its hands," he said.

The Prime Minister expressed hope of a world trade deal being struck at a do-or-die summit in Geneva later this month.

Mr Brown has met leaders of all the major players in the long-stalled Doha round of negotiations, including Brazilian president Luiz Inacio Lula da Silva.

Any Brazilian willingness to accept cheaper imports of western goods such as cars and chemicals could prove the catalyst for European nations, especially France, agreeing to cut support for agriculture.

"The key to a deal is Brazil," he said. "I believe that President Lula is now making possible a resumption of the negotiations with the hope that a deal that has eluded us for months is now possible in the next few days."

French president Nicholas Sarkozy had also been clear in his support for a deal, he said. And British officials said US president George Bush also pushed for it strongly.

Years of negotiations over a trade deal will come to a head at a last-ditch meeting of ministers in Geneva called by World Trade Organisation director general Pascal Lamy for July 21. Arguments over the level of subsidies for farmers in the West and restrictions on the exports of goods from European nations, such as cars and chemicals, to the developing world have been the main sticking point.