Russian President Vladimir Putin said his government was studying the responses from the United States and NATO to Russia's security concerns, but said his country's main complaints "had been ignored."

For weeks Putin had remained tight-lipped about a possible invasion of Ukraine, making scant public remarks about the crisis and the buildup of tens of thousands of Russian troops near the Ukrainian border.But speaking at a Tuesday news conference following a five-hour meeting in Moscow with Hungarian Prime Minister Viktor Orban, the Russian President said: "It is already clear -- I informed the Prime Minister about this -- that the fundamental Russian concerns were ignored. We did not see an adequate consideration of our three key requirements."

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Last year was a historic year for American jobs.

A record number of workers left their employment, while US employers had more positions to fill than ever before.

In December, 4.3 million Americans quit their jobs, down slightly from the record 4.5 million quits in November, the Bureau of Labor Statistics reported Friday.

While millions of workers left jobs for cash incentives, better pay or better benefits -- people also left the labor market to care for their children or elderly relatives during the pandemic.

Meanwhile, older workers retired early either because they could or because age discrimination forced them out of the labor market.

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Tom Brady officially announced his retirement from the NFL via an Instagram post on Tuesday. In the post, Brady said:

"I have always believed the sport of football is an “all-in” proposition - if a 100% competitive commitment isn’t there, you won’t succeed, and success is what I love so much about our game. This is difficult for me to write, but here it goes: I am not going to make that competitive commitment anymore. I have loved my NFL career, and now it is time to focus my time and energy on other things that require my attention."

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Pfizer is expected to seek authorization from the FDA as soon as today for its Covid-19 vaccine for children age 6 months up to 5 years, a person familiar with the plan says.

The company will ask the agency to grant emergency use authorization for a two-dose regimen of its product, while continuing to test three doses in this younger age group, the person said.

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Moderna's Covid-19 vaccine has received full approval from the US Food and Drug Administration, according to news releases from the FDA and Moderna. The vaccine, named Spikevax, is now approved for use in people ages 18 and older. It is not approved or authorized for use in younger individuals. There's no difference between the approved vaccine and the vaccine previously available through emergency use authorization.

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