The United States exerted strained efforts on Sunday to increase diplomatic and financial pressure on Russia over Ukraine, promising to put Moscow on the defensive at the United Nations Security Council as lawmakers on Capitol Hill said they were close to agreeing on "the mother of all sanctions."

According to the US Ambassador to the UN, “The Security Council will press Russia hard in a Monday session to discuss its massing of troops near Ukraine and fears of an invasion.”

It is worth mentioning that the US accused Russia of continuing to intensify its army buildup along Ukraine's border and issued new warnings against any "aggression" by Moscow - accusations Russia has long been denying.

The West had previously threatened Russia with "heavy sanctions", but President Vladimir Putin said Moscow pursues a peaceful foreign policy; however, it has the right to defend its security.

In this context, according to Britain's Foreign Secretary, Liz Truss, Britain will be introducing new sanctions against Russia this week - a legislation which will sanction banks, energy companies, and "oligarchs close to the Kremlin." 

This decision comes a few hours after Britain's announcement that it will be deploying more forces to Estonia in addition to other NATO countries neighboring it.