The Kremlin revealed the details of the conversation between Putin and Biden

He noted that the presidents touched on this topic in a telephone conversation, and the idea was emphasized that in this case, relations would normalize or even improve. Источник The conversation lasted 50 minutes
It was constructive, and not like a “Christmastime gatherings”
We decided that further negotiations would go on 3 tracks
Putin outlined the basic principles of the submitted proposals
Moscow needs security guarantees, and it will seek them
Biden warned of sanctions
Putin replied that in the event sanctions may break relations with the West
Bai Den stressed that a nuclear war should not be started
Biden promised not to deploy offensive strike weapons in Ukraine
Agreed to continue the dialogue in the new year

According to Assistant to the President of the Russian Federation Yuri Ushakov, the success of negotiations between Moscow and Washington on security guarantees will lead to the normalization of bilateral relations. On December 30, Moscow initiated a telephone conversation between the presidents of the Russian Federation and the United States, Vladimir Putin and Joe Biden. According to the American leader, he agreed to hold these negotiations, as “he believes that when it comes to Russia, direct dialogue between the leader and the leader is indispensable.”
The RIA_Kremlinpool Telegram channel has published the details of this conversation.