Vindman retires from Army over 'bullying' by Trump

Lt. Col. Alexander Vindman - who appeared on Capitol Hill last year wearing his military uniform to give damning testimony against the president during the impeachment hearings - retired on Wednesday after more than 21 years of service.

The former member of the White House National Security Council made the decision after suffering what his attorney described as a campaign of "bullying, intimidation, and retaliation" by President Donald Trump.

"It was inappropriate, it was improper for the president to request, to demand, an investigation into a political opponent."

Last year, Vindman, a decorated combat veteran - provided some of the most damaging testimony about Trump's July 25 call with the Ukrainian President Volodymyr Zelensky, which was at the center of the president's impeachment trial.

And in one of the most memorable moments of the congressional hearings, Vindman addressed his father, telling him not to fear for him.

“Dad, my sitting here today in the U.S. Capitol, talking to our elected officials, is proof that you made the right decision 40 years ago to leave the Soviet Union and come here to the United States of America in search of a better life for our family. Do not worry. I will be fine for telling the truth.”

Days after the Republican-led Senate acquitted Trump, Vindman was fired from his position as top Ukraine expert and escorted out of the White House.

By retiring, the 45 year old defuses what could have become a contentious political battle between Senate Democrats and Republicans over an upcoming promotion for Vindman.

With Democrats eager to shield the promotion from political interference and U.S. Senator Tammy Duckworth - herself a veteran - even threatening to put a hold on the confirmation of over 1,000 military promotions until Defense Secretary Mark Esper provided assurances that Vindman's wouldn't be blocked.

A defense official, speaking on condition of anonymity, said Secretary of Defense Mark Esper had approved Vindman for promotion to colonel on Monday as part of a list of promotions due to be sent to the White House.