His comment came after the Supreme Court said government formation in the state would be subject to the final outcome of the case before it.
"Mr Yedyurappa's letter to the Governor will seal his fate. There is no mention of a number bigger than 104. The Governor's invitation does not mention any number at all!," he tweeted.
The former finance and home minister said had he been in Mr Yeddyurappa's place, he would not have taken the oath till the Supreme Court took a decision on the petition filed by the Congress-JD(S) combine challenging the Governor's decision to invite him to take oath.
"I salute the Supreme Court. If I were Mr Yeddyurappa, I will not take oath until the hearing at 10.30 am on Friday, 18th May," Mr Chidambaram said.
The Supreme Court today refused to stay Mr Yeddyurappa's swearing-in as the chief minister after a rare pre-dawn hearing which saw the Congress-JD(S) combine making a last-ditch attempt to stall the BJP's surge in the southern state.
The petition said the Congress-JD(S) combine has the majority in the House with 116 MLAs while the BJP has only 104 seats which was below the majority mark of 112 at present.
The court will hear matter the matter again on Friday.
BS Yeddyurappa took oath as chief minister this morning.
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