K Natwar Singh's ploy of clinging to the Congress to save himself in the Iraq oil for food scam has finally come unstuck.

After he was removed him from the party's steering committee Natwar, on Monday night, said he will resign once the prime minister returns from Russia [Images].

The question is, how did things go wrong for the former minister?

After Congress insider and envoy Aneil Mathrani blew the lid on Natwar's visit to Iraq in 2001, when the oil deals were purportedly struck, the pressure seemed to have shifted on to the Congress and its president Sonia Gandhi [Images] act.

All along, Natwar stood to gain by staying close to the Congress, but the party had to distance itself from him, especially after Mathrani's claims.

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Though the Justice Pathak probe is at a nascent stage, the Congress, as of now, is on very strong legal footing. A source in the ministry of external affairs said there was no documentary evidence against the party in the scam.

Natwar Singh, however, is not so lucky when it comes to the documents obtained by Special Envoy Virender Dayal from the United Nations Independent Inquiry Committee led by Paul Volcker. Sources say these documents show how the oil vouchers were allegedly allotted to Natwar Singh when he visited Baghdad along with a Congress delegation and his son Jagat Singh.   

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The investigators have not just documents of allotment by Iraq's then President Saddam Hussein, but even enough supporting documents. Among these are signatures and bank documents of the people reportedly involved in the scam.

The evidence shows that the same parties executed the allotments to Natwar Singh and to the Congress.

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The documents, however, make no mention of the Congress party as suspected by the Opposition and critics of party president Sonia Gandhi.

A party source said these developments led Sonia Gandhi to believe that Natwar Singh misused the party's name to make money. The end result: the party has distanced itself from Natwar.