The United Liberation Front of Asom has rejected Assam Chief Minister Tarun Gogoi's conditional ceasefire offer.

But the banned outfit said it will consider a proposal of talks with the Centre only if it came out with a 'written commitment to discuss the sovereignty issue'.

A caller, claiming himself to be as ULFA Commander-in-Chief Paresh Barua, told some local dailies over telephone last night that Gogoi was just the head of a 'puppet government put into place by the Centre and he had no authority to present an offer of ceasefire'.

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"Any ceasefire offer with a written assuarance of a discussion on sovereignty must have to come from the Union government. After getting such a gesture from the Centre, ULFA might consider the offer to come to the negotiation table," Barua said.

He further said it was the Centre's sole responsibility to ensure a congenial atmosphere for talks by declaring an unilateral ceasefire.

The Assam government on September 30 had offered conditional ceasefire provided the banned outfit stopped all violence and had asked ULFA to respond within a fortnight so that ceasefire can be declared from October 16.