BJP chief Nitin Gadkari today insisted that the government constitute a Joint Parliamentary Committee to probe the controversial allocation of 2G spectrum. Speaking to reporters in New Delhi, Mr Gadkari questioned if the Prime minister is ready to face PAC, then what is the problem in a JPC probe. He said the government should not decide on who should conduct the inquiry in such a case and should go by the opposition's demand. He said the NDA would hold rallies against corruption tomorrow in different parts of the country.