The United States wants to impose tough sanctions on Russia in the event of further military intervention in Ukraine.

In a phone call with his Russian colleague Vladimir Putin planned for late Thursday evening, American President Joe Biden wanted to promote a diplomatic solution, but also emphasize the willingness to take tough punitive measures, as a high-ranking representative of the White House said.

The Kremlin initially did not respond to the threat from Washington.

Rather, the Kremlin published a New Year's letter from Putin to Biden.

In the telegram, the Kremlin chief advocated a dialogue “based on mutual respect and the consideration of the national interests of the other”.

The two nuclear powers have a special responsibility for international and regional stability, the letter said.

In the face of many challenges and threats to humanity, Moscow and Washington should "work together constructively".

The conversation between Biden and Putin was about a meeting of representatives of both countries in Geneva, planned for January 10, at which the NATO security guarantees demanded by Moscow should also come on the agenda, according to Kremlin spokesman Dmitri Peskov of the Interfax agency according to said in Moscow.

Emergency plans are ready

The representative of the American government said on Wednesday to the address of the Kremlin: "We coordinated with our allies to impose tough sanctions on the Russian economy and the financial system - much more extensive than what was implemented in 2014." At that time Russia annexed the Ukrainian Black Sea peninsula of Crimea and started supporting separatists in eastern Ukraine.

In the event of another Russian invasion of Ukraine, there are already plans to expand NATO's presence in the Eastern European member states and to strengthen their capabilities, said the American representative.

In addition, they are ready to "provide Ukraine with further support to defend its territory and to respond to a possible Russian occupation," he said.

The United States has been accusing Russia of massive troop deployment in areas on the border with Ukraine for weeks.

There are fears in the west of a Russian invasion of the former Soviet republic.

Russia rejects this and again accuses Ukraine of having deployed additional soldiers in the region.

Blinken is on the phone with Selenskyj

The American Foreign Minister Antony Blinken first spoke to the Ukrainian President Volodymyr Selenskyj on Wednesday, and later also in a switch with Federal Foreign Minister Annalena Baerbock and his counterparts from France and Great Britain, as the ministry said.

Washington said they had once again assured their "steadfast support" for the independence, sovereignty and territorial integrity of Ukraine.

Biden and Putin spoke at the beginning of December as part of a two-hour video link.

As heads of state, the two first met in person in Geneva in June.

After the meeting of representatives of Russia and the United States scheduled for January 10 in Geneva, further talks are pending.

NATO is planning a meeting with the Russian side on January 12th.

In addition, there is to be a meeting of the Organization for Security and Cooperation in Europe (OSCE) on January 13th.

Direct military intervention by the US or NATO would be unlikely in the event of a Russian invasion of Ukraine.

Washington and its European allies are more likely to react with drastic economic sanctions.

Among other things, consideration should be given to excluding Russia from the international payments system of the Belgium-based organization Swift.