By Sabine Siebold, John Irish and Humeyra Pamuk

BUCHAREST (Reuters) -NATO allies said on Tuesday they would help Ukraine repair energy infrastructure heavily damaged by Russian bombardments in what NATO’s chief said was Moscow using the descending winter cold as “a weapon of war”.

Russia has been carrying out heavy missile attacks on Ukraine’s power grid and heating infrastructure roughly weekly since October, in what Kyiv and its allies say is a deliberate campaign to harm civilians, a war crime. Russia acknowledges attacking Ukrainian infrastructure but denies deliberately seeking to harm civilians.

“Russia is using brutal missile and drone attacks to leave Ukraine cold and dark this winter,” NATO Secretary-General Jens Stoltenberg said as the alliance’s foreign ministers wrapped up the first of two days of talks in Romania’s capital Bucharest.

“President (Vladimir) Putin is trying to use winter as a weapon of war to force Ukrainians to freeze or flee. He is trying to break the will of the brave Ukrainian people and to divide all of us who support them,” he added.

Stoltenberg was echoed by British Foreign Secretary James Cleverly, who accused Putin of targeting civilian and energy infrastructure “to try and freeze the Ukrainians into submission”.

NATO foreign ministers pledged to step up political and practical support to Ukraine and maintain it for as long as necessary.

“Russia’s aggression, including its persistent and unconscionable attacks on Ukrainian civilian and energy infrastructure, is depriving millions of Ukrainians of basic human services,” they said in a statement.

‘PATRIOTS AND TRANSFORMERS’

Ukraine urged its Western partners to supply it with air defence systems and transformers to blunt Russian strikes.

“If we have transformers and generators, we can restore our energy needs. If we have air defence systems, we can protect from the next Russian missile strikes,” Ukrainian Foreign Minister Dmytro Kuleba said. “In a nutshell: Patriots and transformers are what Ukraine needs the most.”

Stoltenberg said allies were discussing providing Patriot air defence units but cautioned that the systems delivered needed to be effective, maintained and provided with sufficient ammunition, which was a “huge challenge” in itself.

The United States announced it would provide $53 million to buy power grid equipment for Ukraine.

“This equipment will be rapidly delivered to Ukraine on an emergency basis to help Ukrainians persevere through the winter,” a State Department statement said, adding that the package would include distribution transformers, circuit breakers and surge arresters among other equipment.

Foreign ministers also reaffirmed a 2008 NATO summit decision that Ukraine would eventually become a member of the alliance. But, as in 2008, there were no concrete steps or timetable that would actually bring the country closer to NATO.

“We stated that Ukraine will become a member, I expect allies to reiterate that position,” NATO Secretary-General Jens Stoltenberg said at the start of the two-day meeting.

“However, the main focus now is on supporting Ukraine. We are in the midst of a war and therefore we should do nothing that can undermine the unity of allies to provide military, humanitarian, financial support to Ukraine.”

‘KEEP CALM AND GIVE TANKS’

NATO is also pushing arms manufacturers to accelerate production but a European diplomat said there were increasing problems with supply capacity.

Highlighting the view from Baltic states, which have been at the forefront of support for Kyiv, Lithuanian Foreign Minister Gabrielius Landsbergis urged NATO to press ahead with deliveries of tanks, saying the alliance had plenty of them to spare.

“My message to fellow foreign ministers at today’s NATO meeting is simple: Keep calm and give tanks,” he tweeted, showing an image of a Ukrainian flag with a tank in the middle.

Western powers have been reluctant to go down that road for fear it could raise the risk of direct conflict with Russia.

(Reporting by Sabine Siebold, John Irish, Humeyra Pamuk and Luiza Illie in Bucharest, Tom Balmforth in Kyiv and Simon Lewis in Washington and Jason Hovet in Prague; Writing by Sabine Siebold, John Irish and Ingrid Melander; Editing by Ed Osmond, Gareth Jones, Alexandra Hudson and Mark Heinrich)

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