Tesco said the value of its trade with Zimbabwe was "insignificant"
Supermarket chain Tesco has announced it will stop sourcing products from Zimbabwe while "the political crisis persists" there.
The retail giant buys about £1m ($1.9m) worth of goods a year, including vegetables, from Zimbabwe.
Tesco said it was looking for other ways to support workers there.
The move comes a day after a Foreign Office minister urged firms trading with Zimbabwe to "look carefully" at their investments.
The international community has expressed concern at the presidential election re-run, which saw Robert Mugabe claim victory as the sole candidate after opposition leader Morgan Tsvangirai withdrew citing pre-poll violence.
The UN has urged African leaders to try to negotiate a solution to the Zimbabwe's crisis.
Foreign Office Minister Lord Malloch Brown told UK firms that they would find it harder to operate there as sanctions tightened.
Tesco said it had been "a difficult decision" to end its trade with Zimbabwe.
"We cannot ignore the escalating political crisis in Zimbabwe, and the growing consensus in the international community - including from UK politicians on all sides - that further action must be taken to maximise the pressure for change," the company said in a statement.
It added that it was urgently seeking to ensure workers who supplied the retailer and their families were affected as little as possible.
"We cannot continue to support them through trade, but are urgently finding ways to support them by other means," Tesco said.
The retailer had used its concern for Zimbabwean workers as a reason for maintaining its commercial ties with the troubled African nation.
Last week, it said it would be "irresponsible" to withdraw from the country.
Former Africa minister, Peter Hain MP, welcomed Tesco's decision.
"I hope it will give a lead to other British and global companies to freeze or suspend ties with Zimbabwe under Mugabe's tyranny," Mr Hain said.
"This is a decisive time when everybody and every institution in a position to take a stand should do so."
Rival retailers Waitrose and Sainsbury's both buy fish from Zimbabwe.
Waitrose said it supported international efforts to restore democracy and to help the Zimbabwean population.
"We believe our limited relationships with two Zimbabwean suppliers actually enhances these efforts rather than undermining them," Waitrose said.
"In addition, withdrawing our small amount of trade would greatly affect the workers and their extended families."