The United States continues to ramp up diplomatic and financial pressure on Russia over Ukraine, promising to put Moscow on the defensive at the UN Security Council, as politicians say they are nearing agreement on "the mother of all sanctions".
Tensions have soared between Moscow and Washington after Western governments accused Russia of amassing of more than 100,000 soldiers on its border with the former-Soviet, now-independent-republic Ukraine.
The American ambassador to the United Nations said the Security Council will press Russia hard in a session to discuss fears it is planning an invasion.
"Our voices are unified in calling for the Russians to explain themselves," Ambassador Linda Thomas-Greenfield said.
"We're going into the room prepared to listen to them, but we're not going to be distracted by their propaganda."
Ukraine's ambassador to the US, Oksana Markarova, warned that Russian President Vladimir Putin was bent on waging an "attack on democracy", not just on a single country.
"If Ukraine will be further attacked by Russia, of course, they will not stop in Ukraine," Ms Markarova said.
Any formal action by the Security Council is extremely unlikely, given Russia's veto power and its ties with others on the council, including China.
But the US referral of Russia's troop buildup to the UN's most powerful body gives both sides a stage in their fight for global opinion.
Meanwhile, US Senate Foreign Relations Committee chairman Senator Bob Menendez said that, in the event of an attack, politicians want Russia to face "the mother of all sanctions".
That includes actions against Russian banks — that could severely undermine the Russian economy — and increased lethal aid to Ukraine's military.
The sanctions under consideration would apparently be significantly stronger than those imposed after Russia annexed Crimea from Ukraine in 2014.
Those penalties have been seen as ineffective.
Senator Menendez also raised the prospect of imposing some punishments pre-emptively, before any invasion.
"There are some sanctions that really could take place up front, because of what Russia's already done: cyberattacks on Ukraine, false-flag operations, the efforts to undermine the Ukrainian government internally," he said.
Many Republicans are pushing for the US to impose tough penalties instead of waiting for Moscow to send troops into Ukraine.
The Biden administration argues that imposing sanctions now against Mr Putin would remove any deterrent to invasion.
Russia claims 'security is infringed daily'
Russia earlier said it wants "mutually respectful" relations with the US and has denied posing a threat to Ukraine.
"We want good, equal, mutually respectful relations with the United States, like with every country in the world," Russia's Foreign Minister Sergey Lavrov told Russian TV.
He added, however, that Russia did not want to remain in a position "where our security is infringed daily".
Russia is demanding that NATO promise never to allow Ukraine to join the alliance, and to stop the deployment of NATO weapons near Russian borders and roll back its forces from Eastern Europe.
NATO and the US call those demands impossible.
Mr Lavrov said NATO's line of defence continued "moving eastwards" and had come "very close" to Ukraine which, he said, was "not ready" to join NATO.
He also claimed that NATO wanted to pull Ukraine into its alliance, and he challenged its claim of being a purely defensive structure.
NATO "has already come close to Ukraine.", he said.
"They also want to drag this country there.
"Although everyone understands that Ukraine is not ready and could make no contribution to strengthening NATO security."
Mr Lavrov also underlined Russia's contention that NATO expansion is a threat because it has engaged in offensive actions outside its member countries.
Russia's Security Council says talk of threat 'ridiculous'
The head of Russia's Security Council, Nikolai Patrushev, also rejected Western warnings about a planned invasion.
"At this time, they're saying that Russia threatens Ukraine — that's completely ridiculous," he was quoted as saying by state news agency Tass.
"We don't want war and we don't need it at all."
Russia has long-resented NATO granting membership to countries that were once part of the Soviet Union or were in its sphere of influence as members of the Warsaw Pact.
Ukraine has sought NATO membership for years, but any prospect of joining appears far off as the country struggles to find political stability and attack corruption.
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 former Soviet countries.
Russia has also demanded a pullback of NATO forces deployed to eastern European and former Soviet countries that joined the alliance after the Cold War.
The US and NATO have formally rejected Russia's demands about halting NATO expansion, although Washington outlined areas where discussions were possible, offering hope that there could be a way to avoid war.
Russian President Vladimir Putin has made no public remarks about the Western response.
Mr Lavrov has said the response leaves little chance for reaching agreement, though he also says Russia does not want war.
Ukraine has turned, increasingly, to the West since Moscow seized the Crimean peninsula from it in 2014.
That same year, Russia began fuelling a separatist conflict in the east of Ukraine that has claimed more than 13,000 lives.
Those areas have been under the control of Russian-backed rebels since 2014.
On Saturday, Russian politician Viktor Vodolatsky said that residents of those regions feared assaults by Ukrainian forces and that the roughly 500,000 who hold Russian passports would be welcomed in the military.
"If Russian citizens residing in the [territories] want to join the Russian Armed Forces, the Rostov regional military commissariat will register and draft them," Mr Vodolatsky — as deputy chairman of parliament committee on relations with neighbours — told the state news agency Tass.
Western officials to visit Ukraine
Ukrainian President Volodymyr Zelenskyy 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.
Meanwhile, Britain says it is preparing to unveil sanctions against Moscow that will target companies close to the Kremlin.
"There will be nowhere to hide for Putin's oligarchs," UK Foreign Secretary Liz Truss said on Sunday.
Mr 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.
Several Western officials are expected to visit Ukraine in the coming days, including French Foreign Minister Jean-Yves Le Drian, his German counterpart Annalena Baerbock and Polish Prime Minster Mateusz Morawiecki.
Canada's Defence Minister, Anita Anand, arrived for a two-day visit to Kyiv on Sunday, after her government announced it will extend its ongoing training mission in Ukraine and sent non-lethal supplies, such as bulletproof vests.
ABC/Wires
