"They are using food as a ploy to directly control NGOs distributing food and disregard the laws of Zimbabwe," General Vitalis was quoted as saying by the Herald, Wednesday.

"The United States is planning to invade Zimbabwe within the next six months on the pretext of bringing relief food aid to people who were allegedly being denied food on political grounds," the newspaper said, in a front page story.

The two responses follow unusually belligerent remarks made by U.S. principal deputy assistant secretary of state for Africa, Mark Bellamy last week, while participating in a panel discussion on "Famine and Political Violence in Matabeleland" sponsored by the Washington, D.C.-based Center for Strategic and International studies.

"We may have to be prepared to take some very intrusive, interventionist measures to ensure aid delivery to Zimbabwe," Bellamy said. "The dilemmas in the next six months may bring us face to face with Zimbabwe's sovereignty."

"No United States government official has made such a threat," the U.S. embassy in Harare said, reacting to accusations that an invasion plot is being hatched. And a State Department spokesperson in Washington, who would only agree to speak on background, told allAfrica.com that "the concept of a U.S. invasion [of Zimbabwe] is nonsense."

Bellamy was said to be "too busy" to speak to allAfrica.com, Thursday.

Although Bellamy's remarks were unprecedented - not even the long hostility between the United States and Sudan has been so bluntly articulated - few would see an actual U.S. invasion of Zimbabwe as likely. But some kind of direct delivery of food to Matabeleland which, some reports suggest, is being deprived of food aid as political punishment for failing to support the Mugabe government, is not inconceivable.

Relations between Washington and Harare have steadily worsened since Zimbabwe's elections in the spring of this year. "We do not see President Mugabe as the democratically legitimate leader of the country," Assistant Secretary of State for African Affairs Walter Kansteiner said during an August 20 briefing on the southern Africa food crisis. "The election was fraudulent and it was not free and it was not fair."

When specifically asked if he was calling for "regime change," the Secretary responded: "The political status quo is unacceptable... The question is: What are the tactics that we can use to work with those inside Zimbabwe as well as their neighbors to encourage a more democratic outcome? And so we're working with a number of folks in the region and elsewhere."

Amid accusations that Zimbabwe's government is using its control of food distribution to force drought-besieged communities to abandon support of the opposition Movement for Democratic Change, Washington's Africa policymakers have reached agreement that additional pressure needs to be placed on the Mugabe government.

In August, Kansteiner said the U.S. was working with Zimbabwe's neighbors to "isolate" the Mugabe government. But South Africa and the other nations that, along with Zimbabwe, are members of the Southern African Development Community (SADC), have been unenthusiastic about this approach.

The opposition MDC, as well as non-governmental organizations engaged in relief efforts in Matabeleland, may be developing networks to channel food aid into the South where much of the opposition to government is strong. How the U.S. might involve itself with this, and whether it is wise, or might put in jeopardy groups involved in aid efforts, remains unclear.

Asked by allAfrica.com to detail additional measures the U.S. might take, a State Department spokesperson was unwilling to specify anything other than a vague reference to "some sort of additional monitoring"..

Currently, about half of Zimbabwe's 12 million people are affected by drought and in need of food aid. At the end of April, President Mugabe declared a "state of disaster" across the country.