Russian Foreign Minister Sergei Lavrov said on Tuesday that Russia and the United States have made considerable progress on a new nuclear arms reduction treaty.

"We have made significant advancement (on the treaty). At the same time, we have discussed issues which have yet to be negotiated and fine-tuned," Lavrov told a news conference after talks with U.S. Secretary of State Hillary Clinton, who is on a visit to Moscow.

Six rounds of fully fledged talks have been held between the two sides since Russian President Dmitry Medvedev and his U.S. counterpart Barack Obama agreed in London in early April to work out a replacement for the Strategic Arms Reduction Treaty (START-1) , which expires on Dec. 5.

The START-1, signed in 1991, places a limit of 6,000 strategic or long-range nuclear warheads on both countries.

Medvedev and Obama agreed at a July summit in Moscow on the outline of the new arms cuts treaty, including slashing their countries' nuclear arsenals to 1,500-1,675 operational warheads and delivery vehicles to 500-1,000.

In an interview broadcast on Russia's Channel One TV station on Sunday, Medvedev said there is a good chance that Russia and the United States will clinch a new treaty by the end of this year.

"There is certainly a chance for the agreement, since the new U.S. administration has demonstrated interest in this topic," he said.