In more trouble for Finnish mobile firm Nokia, whose immovable assets were attached in an alleged tax evasion case recently, the Income Tax department is set to issue fresh demand notices for payment of taxes to the tune of Rs 1,000 crore.

The department, according to sources, has also "prioritised" the tax demand notices on the firm pertaining to assessment years of 2011-12 and 2012-13 so that the "interest of the revenue" is not jeopardised against the backdrop of the current tax litigation with the company and the proposed acquisition of the mobile-phone maker by US giant Microsoft.

Sources privy to the tax case of Nokia said the firm's assets were frozen not only for the purpose of obtaining revenue with regard to the earlier demand of Rs 2,080 crore, but also in connection with the forthcoming demand notices, which could be issued "as soon as assessment proceedings finish within 2013."

"The estimated fresh tax liability on the firm could be about Rs 1,000 crore and the I-T procedures will be followed in this regard," the sources said.

When contacted by PTI, Nokia said it is unaware of any such forthcoming action and it was not in a position to comment on a prospective move.

"Nokia's longstanding policy is not to comment on market speculation, but we can say that we are unaware of any such claim from the income tax authorities.

"Nokia operates with transparency in its business transactions and is committed to resolving the outstanding issues with Indian tax authorities in accordance with all applicable laws. We are, however, also ready to defend ourselves vigorously as needed," a statement from the official spokesperson of the company said.