Zimbabwe on Monday threatened to expel Western ambassadors it accuses of backing a drive to oust President Robert Mugabe and barred opposition leaders from foreign travel until they appear in court.
Foreign Affairs Minister Simbarashe Mumbengegwi told Zimbabwe state television (ZTV) that he had warned envoys accredited to Harare that Mugabe's government would not hesitate to boot out those who support opposition politics.
"I summoned the ambassadors, and I told them that Zimbabwe will not allow any interference in its internal affairs and that those who are going to continue funding and supporting this program to (remove the government from power) will be expelled," he said during ZTV news bulletin in the local Shona language.
The threat followed a statement by Zimbabwean police that opposition leader Morgan Tsvangirai and his colleagues would be grounded in the country until their case has been dealt with by the courts.
The US ambassador, Christopher Dell, walked out of the meeting after Mumbengegwi failed to give an assurance that the diplomats would be able to respond to his statement, the State Department said in Washington.
"The United States will continue to speak and act steadfastly in support of the people of Zimbabwe's right to democracy," it said in a statement.
Mugabe has come under heavy criticism for a new crackdown on the opposition, which he accuses of trying to organise anti-government protests that he says are bankrolled by some Western countries.
Tsvangirai, head of the Movement for Democratic Change (MDC), and dozens of other opposition figures say they were savagely beaten in police custody. Images of their battered faces prompted a wave of international condemnation of a government which is already battling a severe economic crisis.
Mugabe's government came in for fresh criticism after Tsvangirai's chief spokesman Nelson Chamisa was assaulted and badly injured by a gang at Harare airport on Sunday, forcing him to abandon a trip to Brussels.
At least three other MDC activists were also prevented from leaving the airport over the weekend.
Tsvangirai, Chamisa and dozens of MDC activists face charges of public violence after they were arrested on March 12 at a prayer meeting forbidden under a new ban.
Tsvangirai, who suffered a suspected fractured skull, left a hospital in Harare on Friday. A court hearing on their case last week was canceled and a new date has not been set.
"The case is still pending and they have to appear in court first," police spokesman Wayne Bvudzijena said. "I understand the dockets are ready so the case should proceed anytime."
Defence lawyers for Arthur Mutambara, head of a smaller MDC faction who was arrested as he attempted to travel to South Africa on Saturday, said a Harare Court had on Monday ordered his immediate release.