By VLADIMIR ISACHENKOV

MOSCOW (AP) — Britain’s defense secretary visited Moscow on Friday in another effort to ease tensions over a possible invasion of Ukraine by Russia, which held massive war games near its neighbor and insisted that the highly strained relations were “not at our fault.”

Ben Wallace’s trip came a day after British Foreign Secretary Liz Truss also held talks in Moscow, urging Russia to pull back over 100,000 troops near Ukraine and warning that attacking its neighbor would “have massive consequences and carry severe costs.”

Russia says it has no plans to invade but wants the West to keep Ukraine and other former Soviet countries out of NATO. It also wants NATO to refrain from deploying weapons there and to roll back alliance forces from Eastern Europe — demands flatly rejected by the West.

Speaking at the start of his talks with Wallace, Russian Defense Minister Sergei Shoigu noted that “the military-political situation in Europe is growing increasingly tense, and not at our fault.”

He noted that shipments of weapons to Ukraine by the U.S., Britain and other allies have contributed to the tensions. He also pointed to the recent deployment of British soldiers to Ukraine and inquired why they were sent and how long they will stay.

Speaking to reporters after the talks, Wallace noted that the anti-tank missiles that Britain sent to Ukraine were defensive tactical weapons that do not pose a threat to any neighbor unless it invades.

He said a number of British troops were deployed to Ukraine to help train its military to use the British weapons and will leave fairly soon after they accomplish that mission.

Wallace described the talks as “constructive and frank,” noting his Russian counterpart’s assurances that Moscow has no intention to attack Ukraine. But he also emphasized that the concentration of Russian troops near Ukrainian territory is clearly “beyond normal exercising.”

He warned again that a Russian invasion would have “tragic consequences” and emphasized the need to maintain contacts between military forces to prevent incidents.

In an interview Thursday with NBC News, U.S. President Joe Biden repeated his warning that any Americans still in Ukraine should leave as soon as possible.

“It’s not like we’re dealing with a terrorist organization. We’re dealing with one of the largest armies in the world. It’s a very different situation, and things could go crazy quickly,” he said.

Biden planned to hold a call with trans-Atlantic leaders later in the day.

Asked whether there were any scenarios that would prompt him to send U.S. troops to Ukraine to rescue Americans, the president said: “There’s not. That’s a world war when Americans and Russia start shooting at one another.”

Speaking Friday on a visit to Australia, U.S. Secretary of State Antony Blinken did not detail the reasons behind the latest State Department’s security alert urging all American citizens to leave Ukraine.

“We’re in a window when an invasion could begin at any time and, to be clear, that includes during the Olympics,” Blinken added. The Olympic Games are scheduled to end Feb. 20.

Ukrainian Foreign Minister Dmytro Kuleba played down the U.S. advice to Americans to leave, saying that Washington has made similar calls before. He noted that the situation remains volatile.

Continuing its military buildup near Ukraine, Russia has moved six amphibious assault vessels into the Black Sea, augmenting its capability to land marines on the coast.

Moscow has announced sweeping drills in the Black and Azov seas in the coming days and closed large areas for commercial shipping, drawing a strong protest from Ukraine on Thursday.

Kuleba voiced hope that the West would react to the Russian move, saying that “we have engaged our partners to prepare a coordinated response.”

Russia’s troop concentration includes forces deployed on the territory of its ally Belarus for massive joint drills involving firing live ammunition. Those exercises entered a decisive phase Thursday and will run through Feb. 20. The Ukrainian capital is about 75 kilometers (47 miles) south of the Belarus border.

NATO has stepped up military deployments to bolster its eastern flank, with the U.S. sending troops to Poland and Romania.

The U.S. Navy said Thursday that it has deployed four destroyers from the United States to European waters. The Navy did not directly tie this deployment to the Ukraine crisis but said the ships provide “additional flexibility” to the U.S. Sixth Fleet commander, whose area of responsibility includes the Mediterranean, and will operate in support of NATO allies.

NATO Secretary-General Jens Stoltenberg visited a military base in Romania, hailing the ongoing deployment of 1,000 additional U.S. troops that will nearly double their current number there.

“This is a powerful demonstration of trans-Atlantic unity,” Stoltenberg said.

Russian Foreign Ministry spokeswoman Maria Zakharova responded by noting that “NATO keeps building up its presence near Russia’s borders and exacerbates the situation around Ukraine to create a pretext for that.”

Russia and Ukraine have been locked in a bitter conflict since 2014, when Ukraine’s Kremlin-friendly leader was driven from office by a popular uprising. Moscow responded by annexing Crimea and then backing a separatist insurgency in eastern Ukraine, where fighting has killed over 14,000 people.

A 2015 peace deal brokered by France and Germany helped halt large-scale battles, but regular skirmishes have continued, and efforts to reach a political settlement have stalled. The Kremlin has accused Kyiv of sabotaging the agreement, and Ukrainian officials argued in recent weeks that implementing it would hurt their country.

Foreign policy advisers from Germany, France, Russia and Ukraine held nearly nine hours of talks in Berlin on Thursday to try to revive the stalled agreement but made no progress.

The Berlin talks were part of renewed diplomatic efforts to resolve the biggest security crisis between Russia and the West since the Cold War.

German Chancellor Olaf Scholz, who discussed the standoff with Biden earlier this week, plans to visit Kyiv and Moscow on Monday and Tuesday.

___

Associated Press writers Geir Moulson in Berlin, Yuras Karmanau in Kyiv, Ukraine, and Rod McGuirk in Canberra, Australia, contributed to this report.