HARARE (AFP) - President Robert Mugabe said Friday that "only God" could remove him from office, as Zimbabwe's opposition considered pulling out of next week's run-off election amid escalating violence.

"The MDC will never be allowed to rule this country -- never ever," Mugabe told local business people in Zimbabwe's second city Bulawayo, referring to the opposition Movement for Democratic Change.

"Only God who appointed me will remove me -- not the MDC, not the British."

Mugabe -- in power since independence from Britain in 1980 -- has frequently accused his presidential run-off opponent Morgan Tsvangirai of being a stooge of the former colonial power.

Later Friday, at a rally in Bulawayo, Mugabe said: "We will never allow an event like an election reverse our independence, our sovereignty, our sweat and all that we fought for ... all that our comrades died fighting for."

The MDC plans to meet Sunday to consider whether to contest the June 27 vote, with the party claiming that around 70 of its supporters have been killed since the first round of voting in March.

"In the light of the violence and intimidation, we will make a position whether we still feel the people's will will be realised, whether it's conducive to go into an election," MDC spokesman Nelson Chamisa told AFP.

There were signs the party was deeply split on the issue, with other MDC officials contradicting Chamisa and vowing to press ahead.

Pulling out would likely mean handing victory to Mugabe, who is defying harsh criticism from abroad.

Western powers and human rights groups say the election has been tainted by violence and intimidation, while Tsvangirai alleges that Zimbabwe now is run by what is essentially a "military junta".

"The people have been subjected to violence and intimidation which are so blatant and they are disappointed that we are not having access to the electorate," Innocent Gonese, the MDC's secretary for legal affairs, told AFP.

"People are saying despite all that we should not withdraw and we also believe withdrawing will not solve anything."

Asked about the possibility of pulling out of the election, MDC treasurer general Roy Bennett told AFP in Johannesburg: "That's nonsense. There is no such thing."

Mugabe has vowed the opposition will never come to power in his lifetime and has pledged to fight to keep it from happening.

Referring to Mugabe's remarks, Chamisa said in comments published Friday in the South African newspaper The Star: "What therefore is the point of this election?"

"Why should we participate in it? Many of our members are now wondering and want us to pull out."

Mugabe has threatened to arrest opposition leaders over the pre-election violence, though the United Nations has said the president's supporters were responsible for the bulk of it.

Zimbabwe's police chief Augustine Chihuri said Friday the MDC was the "main culprit to the political violence that we are currently witnessing in the country".

"As the country prepares for a presidential election run-off next week, all necessary force will be applied on malcontents and perpetrators of violence... This violence is aimed at intimidating people from voting and we know it is in preparation of influencing the outcome of the election."

In a case the opposition describes as harassment, a court on Friday refused to dismiss subversion and vote-rigging charges against MDC number-two Tendai Biti, who if convicted faces a possible death sentence.

The magistrate ordered Biti held in prison until at least July 7.

Zimbabwe's attorney general refused to allow bail for Biti later in the day, though his lawyer has appealed to the high court and a hearing has been set for Tuesday.

Biti, the MDC's secretary general, was arrested on June 12 minutes after arriving back in Zimbabwe following a long stay in South Africa. He has been held in prison since then and was officially charged on Thursday.

A harsh critic of Mugabe, Biti faces a total of four charges including subverting the government, election rigging and "projecting the president as an evil man."

Meanwhile, the human rights group Amnesty International urged regional leaders to meet urgently on Zimbabwe's crisis, in a letter written to the head of the Southern African Development Community.

"People are being killed, tortured and subjected to other ill-treatment while the perpetrators are enjoying complete impunity," its secretary general Irene Khan wrote.