New Delhi, April 14 (IANS) The two major Left parties, Communist Party of India-Marxist (CPI-M) and Communist Party of India (CPI), Wednesday called for Minister of State for External Affairs Shashi Tharoor's resignation and said he must step down till his name is cleared of any impropriety in the Indian Premier League's (IPL) Kochi franchise deal.

The CPI even asked Prime Minister Manmohan Singh to demand Tharoor's resignation for misusing his official position.

While asking the government to probe the source of funds flowing into the IPL tournament, the CPI-M said Tharoor's involvement in the Kochi franchise had raised a number of questions.

"It now transpires that a person associated with him has got 19 percent free equity worth Rs.70 crore in the company that led the consortium which got the franchise. The IPL is not just a sporting event but is a big business enterprise in which big money is involved. It is highly inappropriate for a minister in the union government to be involved in such murky dealings," the CPI-M politburo said in a statement here.

"It is incumbent upon Tharoor to step down from office till his name is cleared of any unethical or irregular behaviour."

Asking the government to explain whether its ministers can be involved in business dealings in the name of IPL, the CPI-M asked the government to "reconsider whether any tax exemptions or concessions are justified for this commercial enterprise".

CPI deputy general secretary S. Sudhakar Reddy urged the prime minister to seek Tharoor's resignation. A day earlier the Bharatiya Janata Party (BJP) made a similar demand.

Reddy, who is in Hyderabad, told IANS by phone: "I feel that he (Tharoor) should step down. This is a serious allegation of misuse of power. He is always in the controversy. The prime minister should ask him to quit."

Asked whether the party will raise the issue in parliament, when the second part of the budget session resumes Thursday, Reddy said: "The party MPs will discuss the issue and certainly it will be raised in parliament."

On Tuesday, the BJP demanded a Central Bureau of Investigation (CBI) probe in the Rs.1,530 crore IPL deal in which Tharoor has said he played the role of a mentor and helped the consortium that won the franchise of the Kochi team.

The party alleged that Tharoor misused his official position to secure a stake in the multi-crore rupee IPL deal for his friend Sunanda Pushkar.