The far-reaching proposals, which Russia says are vital for its security, say NATO must not allow any new members to the US-led military alliance and call for no new military bases to be established in ex-Soviet countries.

Their publication comes at a time of severely strained ties between Moscow and Western capitals, where leaders in recent weeks have accused Russia of preparing an invasion of Ukraine.

At a briefing with journalists following the publication of the drafts, Deputy Foreign Minister Sergei Ryabkov said Russia was ready to hold urgent security talks with the United States "as early as" Saturday.

"We are ready to immediately, even tomorrow -- literally tomorrow, on Saturday -- go for talks with the US in a third country," he said, noting that "Geneva was suggested to the Americans".

The release of the unfinished agreements -- an unusual step in international diplomacy -- comes as Washington and Brussels sound the alarm over a build- up of Russian military personnel on Ukraine's borders.

The United States pushed back at the proposals aimed at containing NATO's sphere of influence, saying it would not negotiate without Europe's input.

- 'No talks without European allies' -

"There will be no talks on European security without our European allies and partners," White House Press Secretary Jen Psaki told reporters on board Air Force One.

The West says Moscow has readied some 100,000 troops for an imminent attack and warned Russia of sweeping economic consequences and other steps if it launches an attack.

Russian President Vladimir Putin denies planning an attack and blames NATO for the rise in tensions, demanding "legal guarantees" the alliance won't expand eastwards.

The draft document addressed to NATO says its members should "commit themselves to refrain from further enlargement, including the accession of Ukraine as well as other states".

It also insists that alliance members not conduct military activity in Ukraine or other countries in Eastern Europe, the South Caucasus and Central Asia.

Moscow and NATO, the document said, should agree limits on the deployment of missiles, set up an emergency telephone hotline and also work to "prevent incidents" in the Baltics and the Black Sea.

Those demands come on the back of Moscow's suspension of its mission to NATO earlier and the closure of the alliance's representative office in Moscow after NATO expelled members of Moscow's delegation for spying.

The draft of a security treaty addressed to the United States meanwhile said Washington should block NATO membership of any former Soviet country.

The clause follows demands from Moscow that NATO withdraw a commitment to hand membership to ex-Soviet Georgia and Ukraine.

- 'Impossible' demands -

In the draft, Russia said the United States should agree not to establish military bases in ex-Soviet states, including in Central Asia, which Moscow sees as its backyard and sphere of influence.

The United States leaned heavily on military facilities in ex-Soviet Uzbekistan and Kyrgyzstan to coordinate operations in Afghanistan, where it recently withdrew troops after two decades.

Political analyst Konstantin Kalachev described Russia's list of demands as "unrealistic and impossible" for the United States and NATO to meet.

These "spheres of influence are a thing of the past".

Western countries have discussed possible sanctions against Moscow should Putin launch an attack on Ukraine.

The ongoing conflict in the east of the country erupted after the ouster of a pro-Kremlin president and has left more than 13,000 people dead since 2014.

US President Joe Biden has warned Putin of "sanctions like he's never seen" if an offensive was launched.

European Union leaders this week urged Moscow to halt its military build-up and return to talks led by France and Germany.

The United States and European countries have made clear on numerous occasions that Kiev's membership of NATO is not on the cards, much to Ukraine's annoyance.

But Washington helps train Ukrainian forces and has committed more than $2.5 billion to bolster a military that crumbled in the face of Russia's annexation of the Ukrainian peninsula of Crimea in 2014.

A former KGB agent and loyal servant of the Soviet Union, Putin was dismayed when it fell apart, once calling the collapse "the greatest geopolitical disaster of the 20th century".