Zimbabwean expatriates booed Prime Minister Morgan Tsvangirai when he urged them Saturday during a speech in London to return to their native country.

The audience chanted "Mugabe must go," referring to President Robert Mugabe, The Independent reported. They also shouted "chinja" or "change," turning the slogan of Tsvangirai's Movement for Democratic Change against him.

Tsvangirai, speaking in the Anglican Southwark Cathedral, was so surprised by his audience's reaction that he stopped speaking and left the pulpit for about two minutes.

"I did not say 'pack your bags tomorrow', I said you should be thinking about coming home," he said when he came back.

Tsvangirai, now in a power-sharing government with Mugabe, arrived Friday in London after visits to Washington and Brussels. He is expected to meet with Prime Minister Gordon Brown next week.

The initial welcome for Tsvangirai in Southwark was warm, with a service that began with the singing of the Zimbabwean national anthem and prayers for the country's future. But the audience clearly did not believe Tsvangirai when he said Zimbabwe has already made great strides toward recovery after years of a downward economic spiral under Mugabe.