In his first comments on the cash-for-questions scam involving 11 parliamentarians, Prime Minister Manmohan Singh [Images] on Wednesday expressed "sadness" over the revelation of the lawmakers taking money for raising questions in Parliament.

"I can only express my sadness at such things taking place," Dr Singh told reporters when asked to comment on the joint expose by a website and a news channel.

Both Lok Sabha Speaker Somnath Chatterjee and Rajya Sabha chairman Bhairon Singh Shekhawat have commented on the issue, the prime minister said, adding, "What more could I say on the matter?"

Asked what action he proposed to take on the issue, Singh said, "It is for both Houses of Parliament to determine what
is needed to be done."

Asked about the issue of Volcker Committee report on Iraqi oil payoff, he said he had agreed to respond to the clarifications on his statement in the Rajya Sabha.

"Whatever I have to say on the issue, I will say it there," he said.

Dr Singh arrived in New Delhi later in the night.

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