WASHINGTON — A recommendation to send high-tech tank-killing weapons to Ukraine to help in its fight against Russia is now at the White House, according to three U.S. officials.

The officials said a proposed aid package includes Javelin anti-tank missiles with an estimated cost of about $50 million.

"It is the right move and I see the fingerprints of Secretary of Defense Mattis all over it," said Ret. Adm. James Stavridis, former commander of NATO and an NBC News analyst.

A soldier fires a Javelin during a training exercise of the Estonian Defense Forces on June 19, 2016 near Tapa, Estonia. DOD

"This is a very logical and sensible move which will increase deterrence — because it will place doubt in the minds of Russian aggressors in terms of their use of offensive weapons systems."

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Russia invaded and annexed the Crimea in 2014 and continues to support pro-Russian rebels in eastern Ukraine. The proposal for providing weapons to Ukraine comes amid tension between the White House and Congress over how to respond to Russian interference in the 2016 election, and an investigation by Special Counsel Robert Mueller into possible collusion between the Trump campaign and Russia. President Trump signed a bill imposing sanctions on Russia for its cyberhacking and its actions in Ukraine but complained that it harmed relations.

While the three officials said no final decision has been made on providing the weapons, they agreed that the Pentagon is in favor of the move.

A Russian flag flies near Pro-Russia militants sitting atop a 2S1 Gvozdika (122-mm self-propelled howitzer) as a convoy of pro-Russian forces takes a break as they move from the frontline near the eastern Ukrainian city of Starobeshevo on February 25, 2015 in the Donetsk region. Vasily Maximov / AFP/Getty Images file

A Pentagon spokesperson would not confirm the details of the package, saying only, "we haven't ruled anything out."

"I can certainly say that we have not provided defensive weapons nor have we ruled out the option to do so," said State Department spokesperson Heather Nauert during a briefing Thursday.

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Still undecided, said the three officials, is whether the U.S. would provide the Javelins through an intermediary and whether U.S. service members would train the Ukrainian military on how to operate them.

The most common Russian tank is the T-90, according to Loren Thompson, chief operating officer of the Lexington Institute, a conservative think tank. The Javelin attacks tanks from above, one of the most vulnerable spots of the tank, he explained, adding that other shoulder-fired weapons like an RPG could not take out a Russian tank.

Thompson warned that providing lethal weapons to Ukraine — a country "on Russia's doorstep" — is not without peril for the U.S. "What would we think if the Russians were arming Mexico?" he asked. "This could potentially spark a wider war."

Former Acting CIA Director John McLaughlin, an NBC News analyst, said that the Russians had "earned" the U.S. aid to Ukraine, "but will see it as an escalation even though it poses no immediate danger to their forces given the disposition of the two sides and the nature of the current skirmishing."

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Ukrainian marines prepare to train in urban warfare techniques on the second day of the 'Rapid Trident' bilateral military exercises between the United States and Ukraine that include troops from a variety of NATO and non-NATO countries on September 16, 2014 near Yavorov, Ukraine. file Sean Gallup / Getty Images file

"The U.S. should portray this as an enhancement of Ukrainian defensive capabilities, and part of the deal with Kiev should be that they not use the Javelins to provoke fighting but instead hold onto them for a contingency in which Russia actually uses armor to extend its invasion — which it has not been doing lately."