Italy on Tuesday recalled its ambassador from India in protest over a new delay in the legal proceedings against two Italian marines accused of killing two Indian fishermen.

Ambassador Daniele Mancini will return to Italy immediately for consultations, the foreign ministry said in a statement, condemning "a new and unacceptable delay by the Indian Supreme Court" in a case that has heightened tensions between the two countries.

The two marines, Massimiliano Latorre and Salvatore Girone, who are staying at the Italian embassy in New Delhi, are accused of killing two Indian fishermen they mistook for pirates while guarding a cargo ship in 2012.

"Given India's evident incapacity in handling this case, Italy will continue and intensify action to defend its sovereign rights in line with international law," Foreign Minister Emma Bonino was quoted as saying.

"Italy's main aim remains trying to obtain the return of the two marines as quickly as possible," she said.

A Supreme Court hearing scheduled for Tuesday was immediately postponed because prosecutors are still waiting for the Indian justice ministry to decide which law to try the case under, according to Italian media.

The next hearing will be on February 24.

Italian authorities have lobbied the European Union and the United Nations on the case, saying the two should be tried in Italy because it says the incident took place in international waters.

India denies this, saying it happened in Indian waters.