The United Kingdom warned Kremlin officials on Thursday that it has crafted “high-impact sanctions” with its partners that will be imposed in the case of a Russian invasion of Ukraine.

Roughly 100,000 Russian troops are currently present on the country’s border with Ukraine. Ukraine, a former Soviet state, has diverged sharply from Moscow since the Euromaidan protests, the resignation of Ukraine’s pro-Russian leader Viktor Yanukovych, and Russia’s seizure and annexation of the Crimean Peninsula in 2014.

In response to these developments, Ukraine has cultivated a closer relationship with NATO and has even announced its intention to join the alliance. Russia has insisted that Ukrainian membership in NATO would pose a major threat to its own security because the alliance would have the authority to place missiles practically on Russia’s doorstep.

Consequently, Russian President Vladimir Putin has pushed for a legally binding guarantee that NATO will not allow Ukraine to enter the alliance. NATO officials have so far rejected Moscow’s bold demand.

British Foreign Secretary Liz Truss struck a hard line against Russia, arguing that the Kremlin was “waging [a campaign] to subvert its democratic neighbors.” “They have falsely cast Ukraine as a threat to justify their aggressive stance,” the top British diplomat said, underlining the defensive nature of NATO.

Truss insisted that any further Russian violations of Ukraine’s sovereignty, up to and including a Russian invasion, would lead to “massive consequences” by the Western world, “including coordinated sanctions” that would “impose a severe cost on Russia’s interests and economy.”

“The UK is working with our partners on these sanctions,” Truss said. Although she did not specify what exactly the sanctions would contain, she indicated that they would be aimed at the country’s financial sector.

Russia has repeatedly expressed concerns that NATO expansion up to its borders could pose a major security threat. Putin in particular has argued that, in the absence of any “buffer zone” between Russia and NATO, the Kremlin would have nowhere to retreat to in any potential military conflict.

Truss expected to reiterate Britain’s position in support of Ukrainian sovereignty while visiting Kiev later in the month. She also indicated that the British government was opposed to the opening of the “Nord Stream 2” pipeline, which would deliver gas from Russia to Germany via a pipeline through the Baltic Sea. Truss suggested that the pipeline could lead to European dependence on Russian energy and endanger the independence of the European Union’s foreign policy.

Trevor Filseth is a current and foreign affairs writer for the National Interest.

Image: Reuters.