The United States and Russia say they will resume talks on a new strategic arms reduction treaty at the beginning of next month.
The new START treaty would replace the 1991 agreement which expired in December.
Russian Foreign Minister Sergei Lavrov said Friday the two sides have made significant progress on most issues, and they expect to finalize details when talks resume in February.
In Washington, a spokesman for the National Security Council, Mike Hammer, said the White House is pleased with the progress.
He said National Security Advisor General James Jones and the Chairman of the Joint Chiefs of Staff, Admiral Mike Mullen, had two days of closed-door talks in Moscow with the Russian defense team led by General Nikolai Makarov, chief of the General Staff of the Russian Armed Forces.
U.S. President Barack Obama and his Russian counterpart, Dmitri Medvedev, agreed last year to reduce the nuclear warhead stockpile to between 1,500 and 1,675 for each country.
But American and Russian officials were not able to close the deal during intense negotiations in Geneva in December.
Some information for this report was provided by AP, AFP and Reuters.