The Government does not support calls by Labour for an investigation into the death of the Zimbabwean Prime Minister's wife, says Prime Minister John Key.
Susan Tsvangirai was killed and Morgan Tsvangirai was injured when the car they were in crashed south of the capital Harare on Saturday.
Mr Tsvangirai formed a unity government last month with long-time rival President Robert Mugabe.
A preliminary investigation into the crash, which occurred on a notoriously dangerous stretch of road, has ruled out foul play.
But Labour Party leader Phil Goff says an independent investigation is needed into Ms Tsvangirai's death.
Mr Tsvangirai was flown to neighbouring Botswana for medical tests and rest after the crash.
His MDC party says it will carry out its own investigation into the cause of the crash. Secretary-general Tendai Biti says the accident could have been avoided if a police escort had been provided.
Police say a truck crossed into the opposite lane, sideswiping the prime minister's four-wheel-drive vehicle, causing it to roll over three times.
Mr Tsvangirai and his wife Susan, who married in 1978, have six children.
