Russia has much to be happy about in its new nuclear disarmament treaty with the United States, including a respectable compromise on the hot-button issue of missile defence, analysts said.

With the treaty finally ready after months of difficult negotiations, Russia is now watching warily to see whether it will be ratified by the US Senate, where conservative Republicans have the power to kill it.

Russian analysts described the new treaty as balanced -- an accomplishment in and of itself, given Moscow's hunger to be seen as an equal to Washington after losing the Cold War and suffering a deep decline in the 1990s.

"It is very good for Russia that it reached an agreement which on the whole was fairly even in nature," Roland Timerbaev, a retired Russian diplomat and veteran of US-Soviet arms control talks, told AFP.

"At the end of the day America is more powerful than Russia. This is clear," said Timerbaev, who took part in the original talks on the 1991 Strategic Arms Reduction Treaty (START), which the new agreement will replace.

Moscow has touted the fact that the treaty, due to be signed by US President Barack Obama and his Russian counterpart Dmitry Medvedev in Prague on April 8, includes language linking strategic offensive arms to missile defence.

Russia, which is unhappy about US plans to build missile defences in eastern Europe, had long pushed for such a "linkage" and the issue was one of the main problems dragging out the negotiations.

Washington says its missile defences are meant to protect against the threat of short- and medium-range missiles from Iran and not against Russia's vast arsenal of long-range missiles, but Moscow is still wary of the plans.

The new treaty will impose no restrictions on US missile defences, both US Defence Secretary Robert Gates and Russian Foreign Minister Sergei Lavrov said on Friday after the agreement was announced.

However, Lavrov made it clear that Russia reserved the right to pull out of the nuclear disarmament process if it believed the United States was going too far with missile defence.

"This is a fairly even compromise. There could not have been any limits on missile defence in the treaty, because it is a treaty on strategic arms and not on missile defence," said retired Russian general Vladimir Dvorkin.

"The agreement is balanced and reflects the interests of both Russia and the United States," Dvorkin, who is now an analyst at the Centre for International Security in Moscow, told AFP.

It remains to be seen whether Republican US Senators, who in the past have warned they will not support any deal that harms US missile defense systems, will agree that it is a fair compromise.

Obama needs at least some Republican support to achieve the two-thirds Senate majority necessary to ratify the treaty, which may be a struggle given the highly partisan atmosphere in Washington in recent weeks.

Russia's two houses of parliament -- the State Duma and the Federation Council -- need to ratify the treaty too, but approval will not be a problem because Russian lawmakers do the bidding of the Kremlin, analysts say.

Lavrov however said ratification by the Russian legislature would be done only in "synchronization" with the US Senate, meaning that if lawmakers in Washington block the pact then it could be halted in Russia too.

"Everything will be decided by the US Senate," Alexander Konovalov, head of the Moscow-based Institute of Strategic Assessments, told AFP. "Our Duma is not a barrier. Whatever it is told, it will do."