Zimbabwe, once home to a prosperous agricultural sector, is suffering chronic food shortages in an economic meltdown critics blame on Mugabe's mismanagement. The southern African nation has the world's highest inflation rate -- at more than 165,000 percent.
"Yesterday the (central bank) governor was telling me that they bought over 600,000 tonnes of maize from South Africa," Mugabe said at a campaign rally in northeastern Zimbabwe.
Mugabe, who has ruled Zimbabwe since independence from Britain in 1980, is fighting to hold on to power after opposition Movement for Democratic Change leader Morgan Tsvangirai defeated him in a presidential election on March 29.
Tsvangirai did not win enough votes to avoid a second round.
The Zimbabwean ruler says Tsvangirai is a Western puppet and he accuses British Prime Minister Gordon Brown, U.S. President George W. Bush and other Western leaders of plotting to oust his government for seizing thousands of white-owned farms and redistributing the land to poor blacks.
Mugabe, 84, has expressed confidence he will win the run-off despite his poor performance in the first round when Tsvangirai outpolled him by several percentage points.
"It would be embarrassing for us to be defeated by Tsvangirai," he told supporters at the rally in Shamva district.