Kannur, Feb 24 (IANS): The central government's decision not to invoke the anti-piracy act against the two Italian marines accused of killing two Indian fishermen off the coast of Kerala in 2012, was meant to protect the interests of Congress president Sonia Gandhi, the CPI-M said Monday.

Communist Party of India-Marxist (CPI-M) state secretary Pinarayi Vijayan told reporters here that Monday's decision by the union government to inform the Supreme Court thatthe anti-piracy law would not be invoked came because of an understanding between India and Italy.

"Right from the start of the case, there has been foul play by the centre and at times by Kerala. Through today's decision, it's clear that the interest of Sonia Gandhi has been taken care of," Vijayan said.

"We are all interested to know what state Congress president V.M. Sudheeran has to say on what happened today," he added.

The central government in an affidavit told the apex court Monday that the matter where anti-piracy law could be invoked against two Marines was referred to the law ministry and Minister Kapil Sibal said in his opinion Feb 21 that the "provisions of the SUA Act are not attracted in this case".

Marines Massimilliano Lattore and Salvatore Girone have been held in India since February 2012 when they allegedly shot dead two Indian fishermen off the coast of Kerala, mistaking them for pirates.