Zimbabwe's justice minister has accused the judiciary of overreach and said it had been "captured" by "foreign forces" in order to destabilise the county.

It came after the high court ruled that President Emmerson Mnangagwa's extension of the chief justice's term by five years was illegal.

In a strongly worded statement, the minister, Ziyambi Ziyambi, said they would appeal against the "baseless and meaningless" decision.

"I want to make it clear that we do not accept the decision of the High Court. We have a serious situation of a judiciary that has been captured by foreign forces in this country.

"This is a typical case of judicial overreach and as government, we are not going to accept that," he said.

On Saturday, the court ruled that Luke Malaba, who had just turned 70, had ceased to be chief justice.

The judges said that a recent amendment by parliament, changing the retirement age of senior judges from 70 to 75, had to be put to a referendum.