Congress has demanded an apology from the NDA government for imposing President's rule in Uttarakhand. Briefing reporters in New Delhi this evening, party spokesperson Kapil Sibal also sought the ouster of the minister who advised President's rule in the state. <br/><br/>Mr Sibal alleged that the Constitution is being attacked by the BJP. On drought issue, he said when Parliament is in session and discussing an issue, Prime Minister should have conviction to state his views in Parliament, and not outside.