Archbishop Desmond Tutu's office made a last-ditch appeal Wednesday for South Africa to grant a visa to the Dalai Lama to attend his 80th birthday celebrations.

Deputy President Kgalema Motlanthe tried to tamp down the public outcry over delays with the visa, which prompted the exiled Tibet spiritual leader on Tuesday to cancel his trip, which would have included a peace lecture this weekend.

Motlanthe told local newspapers that "I don't see why it should be an issue at all", and Tutu's Peace Centre urged him to make good on that by granting the visa.

"To the extent that your comments in the Cape Times today suggest that you would have allowed His Holiness into the country, could you please announce unequivocally to the nation that a visa will be granted to His Holiness and he is free to travel to South Africa immediately," the centre's chairman Dumisa Ntsebeza said.

"We appeal to you: rectify the injustice and ensure that His Holiness is granted the visa tomorrow morning," he said in a letter to Motlanthe.

"We feel a grave injustice has been done in the manner in which this matter has been handled -- and tremendous disrespect has been shown to two of the world's greatest spiritual leaders of our times, the archbishop and the Dalai Lama," he said.

Tutu himself has bashed the government's handling of the visa request, calling President Jacob Zuma's administration "worse than the apartheid government".

In an interview with AFP on Wednesday, Tutu had dismissed Motlanthe's remarks and said the government was caving in to China.

"The deputy president says 'no, this thing was in the pipeline'. In the pipeline? It's not weeks before he should have left, it's hours, and why have (they) kept it all so much in abeyance and making everybody uncertain? Why?" Tutu said.

"His explanation just leaves you even more upset instead of making things better. Because you see they could have told us or told the Dalai Lama a heck of a long time earlier 'you are getting the visa or you are not getting the visa'."

"Here we are kowtowing... it's a despicable way," Tutu said.

South Africa has repeatedly denied any influence by China over the visa, and said the Dalai Lama was late handing in his application.

"We are not bullied, we are not pressured, we are not influenced by anybody in making decisions," foreign ministry spokesman Clayson Monyela said.

The Dalai Lama's spokesman Tenzin Taklha said his office had begun the visa process in June, and that on Tuesday the South African embassy in India was not returning their calls.

"His Holiness was scheduled to leave today. It became impossible. He felt it was too much of an inconvenience. His Holiness's policy is not to cause inconvenience to his hosts," he said.

Tutu turns 80 on Friday and had invited his longtime friend and fellow Nobel Peace laureate the Dalai Lama to give an inaugural lecture at his Peace Centre.

As a luminary of the anti-apartheid movement, Tutu is widely regarded as the voice of the national conscience. His condemnation of the government reverberated with other key figures in the struggle for democracy.

"Today all freedom-loving South Africans bow their heads in shame at the brazen insult thrown at two Nobel Peace Prize laureates," said Ahmed Kathrada and Barbara Hogan, both political prisoners during apartheid.

"We are further deeply embarrassed and angered by the inept and unprincipled attempts to justify the delay in granting a visa on bureaucratic grounds. This hints at cowardice and deceit of the worst kind," they said.

About 500 people marched through the University of the Witwatersrand in Johannesburg, where the Dalai Lama would have given a lecture next week, in protest at the visa debacle.

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