He said that all the seven states hit by Left wing extremism -- Chhattisgarh, Orissa, Jharkhand, Andhra Pradesh, Maharashtra, Bihar and West Bengal -- had so far adopted different approaches but what was needed was a joint plan where the "principal focus is on confronting the extremists".

"Left wing extremists have to be confronted squarely and boldly. We have to deal with them firmly and decisively", Chidambaram told reporters here after his meeting with Chhattisgarh Chief Minister Raman Singh and senior state government officials on the naxal issue on Monday evening.

"Broadly, the strategy of Chhattisgarh, it seems, is working as I am told that nearly 40 percent of the area has been regained (from naxals' hold) whereas confrontation with the extremists are going on in another 20 percent area.

However, the extremists have got an upper hand in the rest 40 per cent area," the home minister said.

He said chief ministers of all the seven states hit by Left wing extremism have agreed on a "joint action" to deal with the problem and said it was a significant development.

"I will be visiting all these states to know better about the problem of left wing extremism, Chhattisgarh being the first where I have visited today," he added. Fielding a question on the controversial Salwa Judum (peace campaign) in Chhattisgarh, Chidambaram said the Chhattisgarh chief minister had told him that it was "a spontaneous movement of tribals and the third such movement since 1991."

To a question on Salwa Judum activists taking law into their hands, the union home minister said the Chhattisgarh government and the chief minister have assured him that all actions are being taken by security forces.

"The Chief minister and the government have assured me that actions are being taken by security forces in the areas of Left wing extremism," Chidambaram said, adding "action must remain in the hands of security forces."