Moscow - Differences between the US and Russia over the follow-up to the Strategic Arms Reduction Treaty that expires on December 5 are greater than previously disclosed, Russia media reported Thursday.

Russian Military Chief of Staff Nikolai Makarov confirmed that there have been continued differences over the future number of nuclear warheads and delivery systems, the reports said.

Also unclear is the method which by inspections and control of the disarmament would be carried out.

Plans have it that the number of nuclear warheads would be reduced to a maximum 1,675, while the number of launch systems could be reduced to 1,100. Experts however believe Russia wants deeper cuts than those proposed by the United States.

The US and Russia began another round of talks over nuclear disarmament on Monday in the Swiss city of Geneva. Diplomatic sources said the talks could continue into mid-December.

Until Thursday's reports, statements from the two sides had been general optimistic about the talks, with Russian Foreign Ministry spokesman Andrei Nesterenko a week ago praising the "constructive atmosphere" in disarmament talks with the US.

The Moscow daily Kommersant however reported Thursday that US, despite Russian opposition, wanted "sharper controls" of Russian mobile long-range Topol missiles.

The Interfax news agency quoted General Makarov as saying the Topol missiles were needed in order to maintain the balance of power.

Makarov further criticized that Russia till now had not carried out any inspections in the US. The US inspectors in the Russian city of Votkinsk therefore had to leave Russia when the START agreement expired.

US Secretary of State Hillary Clinton, during her visit to Moscow in mid-October, had spoken of allowing Russian experts to carry out inspections in the US.

Russian Foreign Minister Sergei Lavrov meanwhile warned against a "premature emotionalization" of the disarmament issue, saying that the negotiations were not meant to be held in the public sphere.

Russia and the United States together own 95 per cent of the worlds nuclear weapons. (dpa)