Britain’s David Miliband met with Zimbabwean ambassador to Britain, Gabriel Machinga – a first high-level meeting between the two countries.
Miliband told the House of Commons on Tuesday that he reiterated to Machinga that Britain will not help the country if "signicant changes" are not made.
He told the lawmakers that the political situation remained "very delicate" and said the new Prime Minister Morgan Tsvangirai should be allowed more leverage to make changes in the country.
Miliband said his country’s MPs were "desperate to see an end to the suffering of the Zimbabwean people".
Miliband also said the African continent needed to take development commitments seriously adding that the "wrong response" would be to scale back development commitments, to abandon commitments on trade or to cut ambitions on climate change.
Each of these would harm Africa more than any other continent, he said.
He also told the MPs that the G20 summit this week in London was determined to take "concrete action" to protect the poor and vulnerable.
He said: "The political situation in Zimbabwe remains very delicate indeed yet the meeting of donors in Washington last Friday brought the international community together to focus on humanitarian issues."
He added: "We are also concerned about British nationals in Zimbabwe, a concern that I know will be shared across the House.
"The UK Government recently launched a package offering assistance to elderly and vulnerable people to resettle in the UK.
"These are Britons who are unable to support themselves in Zimbabwe because of the severe economic social and healthcare problems that affect all who live there, something which the new government has barely begun to address."
The meeting between the two leaders is seen as a vital first step in opening up dialogue between Zimbabwe and its former colonizer.