Russia and the United States are wrapping up negotiations on a new nuclear arms reduction treaty to replace START 1, the Russian Foreign Ministry said on Friday.

"Intensive efforts to prepare a bilateral legally binding treaty on further reductions and limits on strategic offensive weapons are close to completion," the ministry said in a statement.

The 1991 Strategic Arms Reduction Treaty, the core of Russian-U.S. nuclear disarmament, expires on Saturday. Officials in Moscow and Washington said recently the new pact is unlikely to be ready by then, but expressed the hope that the document would be signed by yearend.

Presidents Dmitry Medvedev and Barack Obama announced at their first meeting in April that the two countries would replace the START 1 treaty as part of their efforts to "reset" bilateral ties strained in recent years.

Moscow and Washington have been in intensive negotiations since July, when the presidents agreed the treaty''s outline, which included cutting nuclear arsenals to 1,500-1,675 operational warheads and delivery vehicles to 500-1,000.

The chief of the Russian General Staff said earlier that the ongoing talks had thrown up differences on inspection and verification procedures.

The Foreign Ministry said Russian and U.S. negotiators will meet in Geneva on Saturday for the next round of talks. "The negotiations will continue and could last into next week," the ministry said.