U.S. Strategic Command this week is conducting a massive nuclear arms drill designed to "deter and detect strategic attacks" on the United States and allies.

A Sunday press release announcing the May 12-16 "Global Lightning" exercise explicitly noted that the event's timing is "unrelated to real-world events." Observers of ongoing East-West tensions will note, however, that Russia on Thursday conducted its own large-scale nuclear response drill under the supervision of President Vladimir Putin. That exercise was widely promoted in Russian media and included the test launch of an intercontinental ballistic missile and submarine-fired ballistic missiles.

"Exercise Global Lightning 14 has been planned for more than a year and is based on a notional scenario," U.S. Strategic Command said. Roughly 10 B-52 heavy bombers and as many as six B-2 bombers are slated to take part in the nuclear deterrence exercise.

Mark Schneider, a former U.S. Defense Department nuclear strategy official, told the Washington Free Beacon that Russia's drill last week seemed aimed at sending a message of "nuclear intimidation" to the United States and NATO over Ukraine. He noted that Moscow typically stages its atomic exercises in the fall.

Meanwhile, Romania on Saturday sought clarification from Russia on its official policy following a tweet from a high-profile Russian minister that warned he might try to enter Romanian air space in a heavy bomber, Reuters reported.

After a plane he was a traveling in was blocked from entering Romanian air space, Russian Deputy Prime Minister Dmitry Rogozin sent out a tweet that stated, "Upon U.S. request, Romania has closed its air space for my plane. Ukraine doesn't allow me to pass through again. Next time I'll fly on board Tu-160." Rogozin, who supervises his country's large weapons industry, is under U.S. and European Union sanctions.

The Romanian foreign ministry requested that Russia specify whether the deputy prime minister's tweet represented "the Russian Federation's official position."

Romania "believes the threat of using a Russian strategic bomber plane by a Russian deputy prime minister is a very grave statement under the current regional context," the ministry said.