The U.S. and NATO have been building up forces in Eastern Europe and stepping up training exercises ahead of massive Russian war games on the borders of NATO members next month.
Last week, U.S. European Command sent 10 A-10 Thunderbolts and a Special Forces MC-130J Commando II aircraft to Estonia while NATO continued major naval exercises in the North Atlantic, led by the aircraft carrier George H.W. Bush strike group.
In addition, the Pentagon reportedly has been seeking White House approval to send "defensive" arms, including Javelin anti-tank weapons, to Ukraine to guard against Russian-backed separatists who have set up mini-states in eastern Ukraine.
The moves by the U.S. and its allies came as Russia prepared for the huge ground and naval exercise next month called "Zapad," or "West," which Western officials said could involve more than 100,000 military personnel from Russia and Belarus and is shaping up as the largest demonstration of military power during the tenure of Russian President Vladimir Putin.
Belarus borders on Poland, Latvia and Lithuania, all NATO allies. The three Baltic states of Latvia, Lithuania and Estonia, already rattled by snap training exercises called by Putin on their borders, are particularly concerned about the possibility of unintended confrontations during Zapad.
Lithuanian Foreign Minister Raimundas Karoblis has called the Zapad drill a "simulation" for an attack on NATO.
Russian Foreign Minister Sergei Lavrov has scoffed at NATO's concerns and said Zapad will involve no more than 13,000 troops.
However, NATO Secretary General Jens Stoltenberg said at a press conference last month, "We have every reason to believe that it may be substantially more troops participating than the official reported numbers."
Russian officials have said the naval and ground maneuvers will take place Sept. 14-20 in Belarus, the Baltic Sea, western Russia and the Russian exclave of Kaliningrad on the Baltic Sea.
The drills will feature a reconstituted armored force named for a storied Soviet military unit, the First Guards Tank Army, The New York Times reported.
Zapad comes at a time of tense relations between the U.S. and Moscow. Last week, President Donald Trump reluctantly signed a bill passed by veto-proof margins in Congress, increasing sanctions on Russia and requiring the president to go back to Congress if he wishes changes.
Trump charged that the bill infringed on the executive branch's authority on foreign policy.
The debate over the bill also focused renewed attention on Ukraine's long-standing request for "defensive" arms to bolster the "non-lethal" support already supplied by NATO in the form of training, night-vision goggles, radar and other gear.
The Wall Street Journal reported last week that the Pentagon and the State Department now back sending defensive weapons to Ukraine, to include Javelin anti-tank missiles.
In a Pentagon meeting in June with Ukraine's President Petro Poroshenko, U.S. Defense Secretary Jim Mattis said, "We recognize that 2014 was a watershed year for security in Europe," referring to Russia's seizure of Crimea and support for the separatists in eastern Ukraine.
"We also recognize the severe casualties that your people have suffered," he said of the estimated 10,000 killed in the fighting in eastern Ukraine.
"And even in the face of dangers from aggression, cyber attacks and more, a neighbor [Russia] shredding trust, your country has shown a strong commitment to defend itself and, frankly, against all odds," Mattis said. "The United States stands with you."
Poroshenko renewed a standing invitation to Mattis to visit Ukraine and said U.S. support is helping Ukraine to "effectively defend our land against Russian forces."
"We keep our sovereignty, our territorial integrity and our independence significantly because of effective cooperation with our strategic partner, the United States," Poroshenko said.
On July 25 in Paris, Kurt Volker, the U.S. special envoy to Ukraine, confirmed the White House is "considering whether to supply defensive arms to Ukraine; that's where it stands. This is not going to provoke Russia to do more than they already are doing."
If the decision were to supply the arms, it would "give Ukraine an opportunity to defend itself," Volker told Current Time TV, a U.S.-funded news outlet broadcasting to Russia.
The deployment of the A-10s came as the U.S., Britain, NATO allies and partner nations continued the Saxon Warrior naval training exercises in the North Atlantic.
U.S. forces participating included 6,000 sailors from the carrier George H.W. Bush and its strike group, consisting of the guided-missile cruisers Philippine Sea and Hue City, and the guided-missile destroyers Laboon and Truxtun.
Britain is using Saxon Warrior to achieve initial operating capability for the new 920-foot, 70,000 ton carrier HMS Queen Elizabeth, the largest ship ever built for the Royal Navy. The carrier was designed for up to 40 of the F-35B vertical takeoff versions of the Joint Strike Fighter.
U.S. Army Gen. Curtis Scaparrotti, the EuCom commander and NATO's supreme commander, said of the British, "We stand shoulder-to-shoulder here today to help them refine and enhance their carrier strike group capabilities."
The Forward Training Deployment of 270 airmen with the A-10s from the 175th Wing, out of Warfield National Guard Base, Maryland, and an MC-130J Commando II from the 352nd Special Operations Wing, out of Royal Air Force Base Mildenhall in Britain, was made to "increase interoperability and relations between airmen," EuCom said in a statement.
"We are strong members of the NATO Alliance and remain prepared with credible force to assure, deter and defend our allies," said Maj. Gen. Jon K. Kelk, Air National Guard Assistant to the Commander for U.S. Air Forces in Europe and Air Forces Africa. "When we have the opportunity to train with coalition air forces, everyone benefits."
While deployed, the A-10s are scheduled to train with Finnish air force F/A-18 Hornets in Finland and Spanish air force F/A-18 Hornets in Estonia. The A-10s will also work on close-air support with multi-national Joint Terminal Attack Controllers (JTACS) in Latvia, EuCom said.