- Summary- NATO defence ministers meet in Brussels on Wed-Thurs- NATO to hold annual nuclear preparedness drill next week- NATO chief urges Belarus president to stop "complicity"BRUSSELS, Oct 11 (Reuters) - NATO told Moscow on Tuesday it would meet attacks on allies' critical infrastructure with a "united and determined response" and was monitoring Russia's nuclear forces closely as the country was "losing on the battlefield" in Ukraine.Register now for FREE unlimited access to Reuters.com"Russia is actually losing on the battlefield," he told a news conference, saying it was responding with "indiscriminate attacks" to Ukrainian advances.The alliance will proceed with its annual nuclear preparedness exercise "Steadfast Noon" next week, in which NATO air forces practise the use of U.S. nuclear bombs based in Europe with training flights, without live weapons.Russia has made veiled threats of using nuclear weapons against Ukraine, which it invaded on Feb. 24 in what it calls a "special military operation" to demilitarise its neighbour."A deliberate attack against allies' critical infrastructure will be met with a united and determined response," Stoltenberg said."