Russian state-owned gas major OAO Gazprom (GAZP.RS) has proposed a gas supply deal with China National Petroleum Corp. be signed in May when the Russian president Vladimir Putin visits China .

The negotiations between the two companies are on schedule and the agreement will come into effect by the end of 2014, Gazprom said in a statement Wednesday.

Gazprom signed an agreement with CNPC in September on the basic terms for gas supplies but they haven't yet settled the question of price.