South Africa had barred the Dalai Lama from visiting in 2009, saying it did not want to jeopardise ties with China, a key trade partner.

"No such application for a visa by the Dalai Lama has at this stage been received," said home affairs spokesman Ronnie Mamoepa.

He added that ministry officials had twice contacted South Africa's diplomatic mission in New Delhi to verify whether the Buddhist leader had requested a travel document after a Sunday newspaper quoted "diplomatic sources" saying he had applied in June.

The newspaper said Tutu had urged the government to grant a visa to his fellow Nobel Peace Prize laureate, whom he has invited to his 80th birthday celebrations in Cape Town in October.

Tutu strongly criticised South Africa in 2009 for denying entry to the Dalai Lama to attend a peace conference in Johannesburg.

Foreign Minister Maite Nkoana-Mashabane said Monday the Dalai Lama was welcome to visit South Africa and described the earlier decision as poor communication by the government.

The High Commission in New Delhi has been told to inform Pretoria as soon as an application from the Dalai Lama is received, said Mamoepa.

"Upon receipt of such an application, the matter will be given the necessary attention from Pretoria," he added.

The Dalai Lama has lived in exile in India since 1959, when he fled an abortive uprising against Chinese rule in Tibet.

He says he accepts Chinese rule, but Beijing accuses him of being a "splittist" and opposes his regular meetings with foreign leaders.

The 76-year-old recently stepped down as the head of Tibet's government in exile, but he is expected to retain significant influence on major policy decisions.

The outspoken critic of the Communist Party disappeared for nearly three months earlier this year before Chinese authorities, facing a global outcry, announced he had been detained for tax evasion and freed him.

"The worst thing about Beijing is that you can never trust the judicial system. Without trust, you cannot identify anything; its like a sandstorm," Ai wrote in an essay on his native city in the current issue of Newsweek magazine.

"This city is not about other people or buildings or streets but about your mental structure... Beijing is a nightmare. A constant nightmare."

Ai, 54, whose art works have been displayed around the world, said his ordeal in police custody made him realise he was only a number in an anonymous system where "they deny us basic rights".

"Only your family is crying out that youre missing. But you cant get answers from the street communities or officials, or even at the highest levels, the court or the police or the head of the nation," he wrote.

"My wife has been writing these kinds of petitions every day, making phone calls to the police station every day. Where is my husband? Just tell me where my husband is. There is no paper, no information."

Ai further painted Beijing as a city of "power and money" where "those who belong to the government, the coal bosses, the heads of big enterprises" entice foreign investors with their smart suits and business acumen.

"The other city is one of desperation. I see people on public buses, and I see their eyes, and I see they hold no hope," he said of the millions of migrant workers known as "Beijing's slaves".

The essay, which risks further displeasing the authorities, follows a series of anti-government comments posted by Ai on Twitter, where he hit out at the treatment of colleagues and fellow dissidents in an apparent violation of the terms of his bail.

Ai has been barred from leaving Beijing for a year following his detention on charges of tax evasion, which rights groups say was part of a wider crackdown on government critics amid official concern that unrest in the Arab world would spread to China.