US hones warnings, offers to Russia over Ukraine

And, they said there is no chance the U.S. will reduce its military presence or arsenal in Eastern Europe as Russia has demanded.

While those comments, made to reporters on condition of anonymity in a White House-organized telephone conference call, were the first to suggest a willingness to compromise on issues tangential to Ukraine, they were accompanied by threats for Russian inaction on U.S. demands to step back.

In the event of a Russian invasion of Ukraine, “we – in coordination with our allies and partners – would immediately impose severe and overwhelming costs on Russia’s economy, including its financial system and sectors deemed critical to the Kremlin,” another official said.

In addition to sanctions on energy and consumer goods, the U.S. and its allies are considering bans on the export to Russia of advanced electronic components, software and related technology that uses American equipment. Russia could be added to the most restrictive group of countries for export control purposes, together with Cuba, Iran, North Korea and Syria, officials said.

That would mean that Russia’s ability to obtain integrated circuits, and products containing integrated circuits, would be severely restricted, because of the global dominance of U.S. software, technology and equipment in this sector. The impact could extend to aircraft avionics, machine tools, smartphones, game consoles, tablets and televisions.