Britain has pledged £5 million to Zimbabwe but made clear more reforms were needed before it would start large-scale development aid to the shattered country.
British prime minister Gordon Brown told visiting Zimbabwean counterpart Morgan Tsvangirai there were "great signs of progress" in Zimbabwe, but the power-sharing government still had to meet a number of tests on the road to democracy.
Mr Brown announced £4 million of food aid and £1 million for school textbooks, bringing total British "transitional support" for the Zimbabwean government this year to £60 million.
He held out the prospect of more aid if the government, in which Tsvangirai uneasily shares power with President Robert Mugabe, pressed ahead with economic and political reforms.
"We are prepared to go further in offering more transitional support if the reform programme on the ground gains momentum," Mr Brown said, standing by Mr Tsvangirai's side after the first meeting of British and Zimbabwean leaders at 10 Downing Street in more than 10 years.
Zimbabwe says it needs $10 billion to rebuild the economy after a decade of hyperinflation and shortages of basic goods.
The extra British money will be channelled through the World Food Programme and charities.
Like other Western donor countries, Britain remains suspicious of Mr Mugabe and is not yet ready to give direct budget aid to the government.
Mr Tsvangirai formed a coalition government with Mr Mugabe in February. Mr Mugabe has ruled Zimbabwe since independence from Britain in 1980 and has often clashed with London.
Mr Brown said he wanted to see "further rapid steps forward" in Zimbabwe in economic reform - including implementation of International Monetary Fund recommendations and reform of the central bank - and progress on human rights, freedom of the media and the repeal of repressive legislation.
He called for a new constitution within 18 months and elections as soon as possible afterwards, as well as an immediate halt to the seizure of white-owned farms.
"Our support for reform in Zimbabwe does not mean we will turn a blind eye to human rights abuses, corruption and bad governance. We will continue to speak up for those who are intimidated, threatened and exploited," Mr Brown said.
Mr Tsvangirai said Zimbabwe had embarked on irreversible change, noting that inflation had been brought down to about 3 per cent.
He said he was conscious of shortcomings in meeting benchmarks the power-sharing government had set itself "but I can assure you that we will be working very hard to ensure that those conditions are fulfilled," he told Mr Brown.
Mr Tsvangirai told a BBC interviewer that the British state-run broadcaster, banned from operating in Zimbabwe, should be able to send reporters there by July.
Mr Tsvangirai was jeered by Zimbabwean expatriates in London on Saturday when he urged them to return home to help rebuild the ruined economy. Many felt the country remained too dangerous.
"It is unfortunate that those who are living in Britain, because they don't see Mugabe disappear, therefore conclude that nothing has changed. I want to assure you that that is not the case," Mr Tsvangirai told the news conference.
Reuters