Hyderabad: Senior BJP leader M Venkaiah Naidu on Saturday said that union home minister P Chidambaram must resign over the allegation of favouring a former client in a criminal matter, as it was "a clear case of misuse of office".

 "Chidambaram should go. He definitely used his office in withdrawing criminal proceedings against a businessman who had been his client," Naidu said, talking to reporters here.

Dismissing the union government's claim that Chidambaram had no knowledge of the letter written by an officer in the home ministry, Naidu read out the letter written by A K Saxena, a director in the ministry, to Delhi government on May 9 this year, asking it to take urgent action for withdrawal of prosecution.

Naidu said the officer had clearly mentioned in the letter that "this has approval of the Union Home Minister". How an officer could write a letter without the minister's knowledge, Naidu said.

Alleging that the union government as well as Chidambaram were misleading the people, Naidu said that BJP would take the issue to 'its logical end'.