A contract for the delivery of S-400 Triumf missile systems to India won’t be signed during the current visit by Indian Defense Minister Nirmala Sitharaman to Moscow, a source in military-diplomatic circles told TASS on the sidelines of the Moscow international security conference on Wednesday.

"All the technical parameters of the contract have been fully agreed; however, the sides have not yet agreed on the price of the deal," the source said.

Some media outlets earlier reported that India and Russia were close to signing a contract on the delivery of S-400 air defense missile systems and that its signing might take place during Sitharaman’s visit to Moscow.

At the same time, the source was optimistic about the prospects of signing the S-400 deal.

"The sides are continuing the negotiations on this sole issue that has not yet been agreed and there are no doubts that the document will be signed shortly," the source noted.

TASS has no official confirmation of this information.