It was Mugabe's first major speech since last month's disputed election, which opposition party Movement for Democratic Change claims to have won.
"Down with the British. Down with thieves who want to steal our country," Mugabe said, according to Reuters.
"Today they are like thieves fronting their lackeys among us, which they give money to confuse our people."
Mugabe's heated remarks were made at an Independence Day celebration, in front of 15,000 people at a Harare stadium, reported The New York Times. He was given a rousing reception by his supporters, many of whom wore shirts with his image on them.
Results from the March 29 presidential election still have not been released.
The MDC candidate Morgan Tsvangirai is believed to have won, but possibly by a small enough margin that a runoff would be necessary.
Two top members of Mugabe's party said Friday that he has deployed the army and police to intimidate voters in rural areas to make sure he would win a potential runoff, Bloomberg reported.
The MDC has accused Mugabe, who has been in power since 1980, of delaying the results to orchestrate a way to remain president. The party has refused to participate in a runoff and tried to challenge a bid for a partial election recount.
The Harare High Court on Friday rejected the request to block the recount, which could overturn the MDC's parliamentary vote win. Mugabe's party lost control of the parliament for the first time in March's elections.
For several days after the election there was speculation that Mugabe would leave the country, but his Friday remarks reinforced that he will not turn over power.
Zimbabwe has been under mounting international pressure to release the election results.
U.S. President Bush and Secretary of State Condoleezza Rice called for more action from neighboring African nations to end the crisis in Zimbabwe on Thursday.
Rice described Mugabe's last few years of rule as an "abomination."
The government of South Africa, which tried to distance itself from the election deadlock, called the situation in Zimbabwe "dire" on Thursday.
"When elections are held and results are not released two weeks after, it is obviously of great concern," said government spokesman Themba Maseko, according to the International Herald Tribune.
"South Africa, like the rest of the world, is concerned about the delay in the release of the results and the anxiety that this is generating."
The British Embassy in Harare released a statement on Friday expressing concern "at reports of beatings and violence being unleashed against electoral officials and opposition supporters."
Meanwhile, South African port and truck workers are refusing to move Zimbabwe-bound weapons from a Chinese ship, union officials told the Associated Press Friday.
The An Yue Jiang ship was anchored just outside Durban harbor after receiving permission late Wednesday to dock.
"This vessel must return to China with the arms on board, as South Africa cannot be seen to be facilitating the flow of weapons into Zimbabwe at a time where there is a political dispute and a volatile situation," the Congress of South African Trade Unions said in a statement.
The Southern Africa Litigation Center, an independent human rights group, said it has asked a court to stop the arms from being transported to Zimbabwe.
Mary Robinson, the former U.N. human rights chief, applauded the unions for taking a stand.
"How positive it is that ordinary dockers have refused to allow that boat to go further," Robinson said during a conference in Senegal on governance in Africa. "They as individuals have taken the responsibility. Because they believe it's not right."