"Either the Prime Minister or Shinde should either confirm or denounce it as it involves the reputation of Muslims," BJP national spokesperson Syed Shahanwaz Hussain told reporters here.
"Rahul has made serious allegations against Muslims and insulted them by linking them to the ISI," he said.
He said it deserved downright condemnation as it has not been confirmed by the government that the ISI and some victims of Muzaffarnagar riots were in contact with each other.
He said that the Congress should remember the riots, including the one in 1984, had taken place when the party was in power at the Centre or in states.
With the Muzaffarnagar riots generating heat in Uttar Pradesh politics, Hussain also asked the Samajwadi Party to take a stand on the issue.