Russian-Belarusian Zapad military exercises in Kaliningrad region, in 2013 | Pool photo by Alexey Novosti/EPA US and Russia clash over military exercises But Moscow’s ambassador to NATO says the West is to blame for rising tension.

PAPA AIR BASE, Hungary — As thousands of U.S. troops drilled for a potential land war to protect NATO allies, the commander of U.S. Army forces in Europe urged Russia to be more transparent about its own upcoming major military exercise and ease anxiety by allowing outside observers.

The Russian exercise, called Zapad (meaning West), is scheduled for September and is part of a rotation of annual drills focused on Russia's geographically-defined military districts.

The American commander, Lieutenant General Ben Hodges, who leads the U.S. Army Europe from a base in Wiesbaden, Germany, said that Russia's neighbors were anxious and called for greater transparency. His comments drew forceful pushback from Russia's ambassador to NATO, Alexander Grushko, who accused the West of fear-mongering and said NATO had escalated tensions by increasing its presence in Eastern Europe.

"Everybody that lives close to the Western military district is a little bit worried because they hear about the size of the exercise," Hodges said at a news conference Tuesday at Papa Air Base in northwest Hungary. "The Russian Federation could do a lot to reduce anxiety if they would be more transparent, exactly what you see here: what Hungary allows at exercises in Hungary is media, visitors, and that transparency helps reduce tension."

Hodges added, "I would ask that the Russian Federation do the same thing."

In response to questions from POLITICO, Ambassador Grushko issued a statement saying it was the West, not Russia, that was provoking anxiety through its efforts to build new "deterrence" capabilities in Eastern Europe — and that Russia routinely invited journalists and other monitors to observe both drills and active military operations, such as those in Syria.

"We continue to see new propaganda stories around the Russian-Belarusian exercises Zapad-2017, attempts to 'demonize' them," Grushko said. "We have seen reports that NATO countries intend to build up military presence near the areas where these maneuvers will be conducted. This raises concerns and may lead to increased risks of incidents."

"The root causes for the aggravation of the situation lie in the progressive build-up of the NATO military presence and activities on the so-called eastern flank," Grushko said.

"NATO’s enhanced forward presence is being maintained in close proximity to Russia's borders," he added. "If NATO countries are really concerned about the unstable situation in the region, then firstly what they need to do is to curtail their own military activities, which are groundless and contradict the real security needs."

Relations between Russia and the West deteriorated sharply after Moscow's invasion and annexation of Crimea in 2014 and its subsequent military intervention in eastern Ukraine, where an armed conflict continues to simmer and there has been little success in implementing a peace agreement known as the Minsk 2 accord.

Allies, including the EU, U.S. and Canada, have imposed economic sanctions intended to punish Russia, and the Kremlin has imposed counter-sanctions. Meanwhile, anxiety among Eastern European nations has led NATO to increase its military presence in the region. NATO's new "deterrence" posture has included the stationing of multinational battle groups in Poland, and the Baltic nations of Estonia, Latvia and Lithuania.

Risk warning

The Center for European Policy Analysis, a Washington based think-tank focused on Central and Eastern Europe, has published a paper by two Polish experts warning of the risks posed by Russian military exercises and noting that substantial new Russian military resources had been moved into westward positions, including in the enclave of Kaliningrad, between Poland and the Baltic states.

"Thanks to this military build-up, all under the pretext of the Zapad exercise, Russia’s options are many," the authors of the paper, Tomasz K. Kowalik and Dominik P. Jankowski, wrote. "It could, with little or no warning, launch a limited or provocative hybrid operation (to see what happens), test responses on NATO’s eastern flank, or present a security threat to Ukraine where the Russo-Ukraine conflict remains in full swing."

After a meeting of the Russia-NATO Council last week, NATO Secretary-General Jens Stoltenberg said that Russian officials had offered a briefing about the Zapad exercise but that there was good reason for the alliance to be skeptical.

"From previous experiences related to previous exercises, we have every reason to believe that it may be substantially more troops participating than the official reported numbers," Stoltenberg said at a news conference.

Grushko said the West had no reason to doubt Russia's intentions.

"Russia strictly abides by all existing agreements related to ensuring predictability and transparency of military activities," he said in his statement to POLITICO. "Our country is one of the leaders in terms of using the instruments of confidence and security-building measures."