Moscow (AFP) - Russia said Sunday it wants "mutually respectful" relations with the United States and denied posing a threat to Ukraine, as the UK said it was preparing fresh sanctions against Moscow. 

Tensions have soared between Moscow and Washington after Western governments accused Russia of amassing tens of thousands of troops on its border with ex-Soviet Ukraine.

The military build-up has sparked fears that Russia is planning an invasion, spooking NATO and its members in the region and prompting the Western alliance to explore bolstering its own deployments there.

"We want good, equal, mutually respectful relations with the United States, like with every country in the world," Russia's Foreign Minister Sergei Lavrov told Russian TV on Sunday.

He added, however, that Russia doesn't want to remain in a position "where our security is infringed daily".

Citing the encroachment of NATO near its eastern border, Russia has put forward security demands to Washington and the US-led military alliance. 

These include a guarantee that NATO will not admit new members, in particular Ukraine, and the United States will not establish new military bases in ex-Soviet countries. 

Russia has also demanded a pullback of NATO forces deployed to eastern European and ex-Soviet countries that joined the alliance after the Cold War

Lavrov said that NATO's line of defence "continues moving eastwards" and has come "very close" to Ukraine, which according to him, is "not ready" to joint NATO.

Western leaders have scrambled to diffuse the crisis by reaching out to Russian President Vladimir Putin, while also vowing unprecedented sanctions should Moscow launch an attack. 

'We don't want war'

Ukrainian President Volodymyr Zelensky has called on the West to avoid stirring "panic" in the face of the Russian troop build-up, while his foreign minister Dmytro Kuleba said it was important to remain "firm" in talks with Moscow.

Britain said it is preparing to unveil sanctions against Moscow that would target companies close to the Kremlin. 

"There will be nowhere to hide for Putin's oligarchs," UK Foreign Secretary Liz Truss said Sunday.

Putin on Friday held a phone call with French President Emmanuel Macron and Britain's Boris Johnson is expected to speak with the Russian leader next week.  

Russia has repeatedly denied planning an attack and said it's not looking to start a war. 

"We don't want war. We don't need it at all," Nikolai Patrushev, head of Russia's powerful Security Council, told reporters on Sunday. 

He added that Russia poses no threat to Ukraine.

"Even the Ukrainians, including officials say there is no threat," Patrushev said. 

Following a flurry of diplomatic efforts over the past weeks, Washington and NATO presented Moscow with a written response to its security demands.

Russia said the replies, which were not made public, did not address its main concerns but did not rule out further talks.

Ukraine has turned increasingly to the West since Moscow seized the Crimea peninsula in 2014 and began fuelling a separatist conflict in the east of the country that has cost over 13,000 lives. 

In the face of Russia's latest build-up, some Western allies -- led by the US -- have stepped up deliveries of arms to Kyiv that could be used to ward off an attack.