By Steve Holland

WASHINGTON (Reuters) -The United States is concerned that Russia is preparing for an invasion of Ukraine soon by fabricating a pretext for war if diplomacy fails to meet its objectives, the White House said on Friday.

Talks between the United States, its European allies and Russia ended in a stalemate this week with no current plans to meet again about Russia’s deployment of tens of thousands of troops along Ukraine’s border. A cyber attack against Ukraine has further inflamed tensions.

A spokesperson for the White House National Security Council said it was not yet clear who was responsible for the cyber attack but that President Joe Biden had been briefed on it.

“We are in touch with the Ukrainians and have offered our support as Ukraine investigates the impact and nature and recovers from the incidents. We don’t have an attribution at this time,” the spokesperson said.

Biden has warned of severe economic consequences for Russia if Russian President Vladimir Putin launches an invasion of Ukraine. Russia denies plans to attack Ukraine and has demanded NATO stop its eastward expansion and agree to legally binding security guarantees, demands that the United States and NATO have rejected.

White House press secretary Jen Psaki told reporters the United States is concerned the Russian government “is preparing for an invasion into Ukraine that may result in widespread human rights violations and war crimes should diplomacy fail to meet their objectives.”

“As part of its plans, Russia is laying the groundwork to have the option of fabricating a pretext for invasion, including through sabotage activities and information operations, by accusing Ukraine of preparing an imminent attack against Russian forces in eastern Ukraine,” Psaki said.

The Russian military “plans to begin these activities several weeks before a military invasion, which could begin between mid-January and mid-February,” she said.

Psaki said it is up to Putin to determine the path forward, and that a tough U.S. response awaits should he launch an invasion.

“If they decide they want to engage in diplomatic conversations and talks, we are very open to that and we’re hopeful they will do that. But ultimately, it’s a choice they need to make,” she said.

‘FALSE-FLAG OPERATION’

A U.S. official said the United States has information that indicates Russia has already positioned a group of operatives to conduct “a false-flag operation” in eastern Ukraine.

“The operatives are trained in urban warfare and in using explosives to carry out acts of sabotage against Russia’s own proxy-forces,” said the official, who spoke on condition of anonymity.

The official also said that indications are that “Russian influence actors are already starting to fabricate Ukrainian provocations in state and social media to justify a Russian intervention and sow divisions in Ukraine.”

Pentagon spokesperson John Kirby said if history was a guide, it would be difficult to see these kind of activities without the knowledge of senior Russian leaders.

Asked whether the U.S. military would continue to support Ukrainian forces with security assistance in the event of a Russian invasion, Kirby said: “We have and we will continue to provide security assistance to Ukraine to help them better defend themselves.”

(Reporting by Steve HollandAdditional reporting by Alexandra Alper and Idrees AliEditing by Chizu Nomiyama, Alistair Bell and Frances Kerry)

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