One week after the Congress plunged into a crisis in Kerala, president Sonia Gandhi has decided to side with Chief Minister A K Antony and act tough with veteran politician and former chief minister K Karunakaran.

Gandhi, who has refused to talk to Karunakaran, has passed on a message to him through his son, Kerala Pradesh Congress Committee president K Muraleedharan, that any act of indiscipline will not be tolerated.

The stern warning came after the senior leader put up a rebel candidate for the forthcoming biennial Rajya Sabha election.

Party officials said Muraleedharan has informed Karunakaran about the party leadership's stand.

Muraleedharan, who was also upset by the decision to nominate candidates suggested by Antony and submitted his resignation as KPCC president, is in New Delhi holding talks with Gandhi and other senior party politicians.

Muraleedharan's aides, however, said he will withdraw his resignation in a day or two as Gandhi has already requested him to do so. "Muraleedharan resigned on the spur of the moment," a supporter said. "He will not press his resignation now after discussions with the Congress president."

Congress general secretary Vayalar Ravi and Thennala Balakrishna Pillai are the party's official candidates, nominated by Gandhi in consultation with Antony.

But miffed at Gandhi's refusal to name a politician of his choice as candidate, Karunakaran has put up Kodoth Govindan Nair as a rebel.

This virtual revolt has worsened the infighting between the Karunakaran and Antony factions.

State Congress politicians disclosed that Gandhi is 'very upset' with Karunakaran's pressure tactics aimed at weakening Antony's government. "Gandhi has even refused to talk to Karunakaran on the telephone," a senior politician close to Antony told rediff.com "The only way out for him now is to pull out his rebel nominee or face disciplinary action."

He said the high command had always been supportive of Antony and his leadership in the state. "Karunakaran has unnecessarily created a crisis," the politician said.

Already, Congress general secretary Ambika Soni, who is in charge of Kerala, has warned that Karunakaran's nominee will be suspended if he does not pull out of the race by April 14, the last day for withdrawals. Many believe that if this happens, Karunakaran is likely to walk out of the party.

But senior Congressman Oommen Chandy remains optimistic that the crisis will be resolved by taking into consideration the feelings of all senior leaders.

Chandy said the crisis does not pose any threat to the survival of Antony's government despite the opposition's claims otherwise. "We do not have the time to listen to their rumour-mongering," he said.