Zimbabwean envoy Boniface Chidyausiku said British Prime Minister Gordon Brown has no right to dictate who can attend the the EU-African Union summit in Lisbon in December.
He told the BBC that Mr. Brown is trying to drag other parties into what he called a disagreement between Britain and its former colony.
"We have said the quarrel is between Britain and Zimbabwe," he said. "The United Kingdom government has had the tendency of trying to put this quarrel into a multilateral forum. Really a meeting between Europe and Africa should go ahead, and there are more bigger issues to discuss than the differences between Britain and Zimbabwe."
This follows an article written by Mr. Brown and published in newspaper on Thursday. The British prime minister said he would not attend the summit, the first in seven years, if Mr. Mugabe attends.
He said Mr. Mugabe's participation would divert attention from important issues that need to be resolved on the continent.
Mr. Brown said the Zimbabwean leader's attendance would mean that a European Union travel ban on Mr. Mugabe and other Zimbabwe officials, imposed for alleged human rights abuses, would be suspended.
The prime minister blamed Mr. Mugabe for the economic meltdown and dire living conditions in Zimbabwe. He said unemployment in the African country is now 80 percent and that four million people will depend on food aid by the end of the year.
Mr. Brown said the travel ban may be extended to include more individuals close to Mr. Mugabe and that he wants to put pressure on the U.N. Security Council to send a humanitarian team to Zimbabwe.
But reaction to Mr. Brown from fellow European Union members has been mixed.
A report in Friday's newspaper quotes the EU's development and aid commissioner as saying the summit must go ahead. Louis Michel said the disagreement between Britain and Zimbabwe should not be allowed to get in the way of the two continents meeting.
Zambia's President Levy Mwanawasa announced on Thursday that he will boycott the summit if Mr. Mugabe is not invited. He added that he could be joined by other African leaders.