Hyderabad, June 11 (IANS) Terming the government's white paper on black money as a lie paper, yoga guru Baba Ramdev Monday said Prime Minister Manmohan Singh of working under pressure and was not even able to smile.

Addressing a joint press conference with Telugu Desam Party (TDP) party chief Chandrababu Naidu, Baba Ramdev said the prime minister was under pressure.

He is always under pressure. That's why he is not even able to smile, Ramdev said.

Answering queries, he said the prime minister was personally honest but he had to display political and constitutional honesty.

Ramdev said that an agitation would be held Aug 9 against black money and corruption.

He said gold accounted for the largest amount of black money in the country and sectors such as real estate and mining also had a large amount of the ill-gotten money.

The white paper (on black money) is a lie paper, he said.

Naidu extended his party's support to Ramdev's agitation against black money and corruption.