The Centre on Friday said the security forces are moving "cautiously" in their operation against Maoists in trouble-torn Lalgarh in West Bengal and it would take some more time before they complete the task.

"The operation will take considerably more time as security forces are moving towards Lalgarh cautiously. They are also addressing people through loudspeakers and distributing handbills," Home Minister P Chidambaram told reporters in the capital.

He added that the forces should expect the "unexpected".

The Home Minister further said operation in Lalgarh was not aimed at local tribals but at the Naxals who have taken control of the area.

"The operation is not against tribals but the Naxals," he said.

Chidambaram said the action against the Maoists were going on according to the plan and it would be successful soon.

"Adequate number of state police have been deployed there. The state police are taking the lead and the CRPF personnel are assisting in the operation," he said.

Chidambaram also said he endorsed the appeal of West Bengal Chief Minister Buddhadeb Bhattacharjee to the Maoists and the tribals to come for talks.

"I endorse that appeal. If they wish to talk, they should come forward to do so. We will be happy to facilitate the talks," he told reporters after a Cabinet meeting.