Washington (CNN) President Donald Trump's senior aide Jared Kushner and ousted adviser Michael Flynn met with the Russian ambassador to the United States at a time when the Trump administration's relationship with the Russians was under close scrutiny.

Kushner and Flynn sat down in December at Trump Tower with Sergey Kislyak , according to a senior administration official, who described it as an "introductory meeting" and "kind of an inconsequential hello."

The meeting lasted for about 10 minutes, the official added.

Flynn was fired from his role as a national security adviser after he misled the administration about his conversations with Kislyak, and Attorney General Jeff Sessions on Thursday said he would recuse himself from investigations into the Trump campaign relationship with Russia after news emerged that he too had spoken privately with the ambassador.

Kushner's involvement in a meeting was first reported by The New Yorker, and Flynn's by The New York Times.

The administration official disputed the idea that accepting a meeting with the Russian ambassador could be cause for concern in light of the discussion about Russian meddling in the US election , characterizing the meeting as merely an attempt to meet key international players during the transition to power. The official added that Kushner met with dozens of other ambassadors.

Photos: President Trump's first address to Congress Photos: President Trump's first address to Congress US President Donald Trump addresses a joint session of Congress for the first time on Tuesday, February 28. Behind him, from left, are Vice President Mike Pence and House Speaker Paul Ryan. Hide Caption 1 of 22 Photos: President Trump's first address to Congress Trump speaks at the beginning of his address. Hide Caption 2 of 22 Photos: President Trump's first address to Congress A wide view of the House chamber. Hide Caption 3 of 22 Photos: President Trump's first address to Congress Supreme Court justices watch the speech. From left, in front, are John Roberts, Anthony Kennedy, Stephen Breyer, Sonia Sotomayor and Elena Kagan. Hide Caption 4 of 22 Photos: President Trump's first address to Congress Maureen Scalia, the widow of late Supreme Court Justice Antonin Scalia, is applauded during the speech. Hide Caption 5 of 22 Photos: President Trump's first address to Congress Carryn Owens, center, cries as she is applauded by the chamber during Trump's speech. Owens' husband, Navy SEAL William "Ryan" Owens, recently was killed during a mission in Yemen. "Ryan died as he lived: a warrior and a hero, battling against terrorism and securing our nation," Trump said. The applause lasted over a minute, which Trump said must be a record. Hide Caption 6 of 22 Photos: President Trump's first address to Congress Trump also recognized Megan Crowley, a college student who, at 15 months old, was diagnosed with Pompe disease and wasn't expected to live past age 5. Her father founded a pharmaceutical company to find a cure. "Megan's story is about the unbounded power of a father's love for a daughter," Trump said. "But our slow and burdensome approval process at the Food and Drug Administration keeps too many advances, like the one that saved Megan's life, from reaching those in need." Hide Caption 7 of 22 Photos: President Trump's first address to Congress Muslim activist Fauzia Rizvi, a guest of US Rep. Mark Takano, watches Trump's address. Hide Caption 8 of 22 Photos: President Trump's first address to Congress Members of Trump's Cabinet applaud the President. From left are Defense Secretary James Mattis, Education Secretary Betsy DeVos, Attorney General Jeff Sessions, Treasury Secretary Steve Mnuchin and Secretary of State Rex Tillerson. Hide Caption 9 of 22 Photos: President Trump's first address to Congress Trump smiles during his speech, which lasted over an hour. Hide Caption 10 of 22 Photos: President Trump's first address to Congress House Minority Leader Nancy Pelosi listens to the speech. Hide Caption 11 of 22 Photos: President Trump's first address to Congress The President waves before starting his speech. Hide Caption 12 of 22 Photos: President Trump's first address to Congress Trump is applauded after arriving in the House chamber. Hide Caption 13 of 22 Photos: President Trump's first address to Congress Trump shakes hands with Ryan before starting. Hide Caption 14 of 22 Photos: President Trump's first address to Congress Trump shakes hands on his way through the chamber. Facing the President here are Health and Human Services Secretary Tom Price, left, and UN Ambassador Nikki Haley. Hide Caption 15 of 22 Photos: President Trump's first address to Congress Trump stands in the doorway of the House chamber while being introduced. Hide Caption 16 of 22 Photos: President Trump's first address to Congress Pence confers with Ryan before Trump's speech. Hide Caption 17 of 22 Photos: President Trump's first address to Congress First lady Melania Trump, bottom right, is applauded as she arrives in the chamber. Hide Caption 18 of 22 Photos: President Trump's first address to Congress US Sen. John McCain, left, talks with US Sen. Lindsey Graham before Trump arrived. Hide Caption 19 of 22 Photos: President Trump's first address to Congress US Sens. Cory Booker and Bob Menendez arrive in the House chamber. Hide Caption 20 of 22 Photos: President Trump's first address to Congress Many Democrats wore white as a nod to the women's suffrage movement. Posing for a photo here are, from left, US Reps. Brenda Lawrence, Joyce Beatty, Marcia Fudge and Val Demings. Hide Caption 21 of 22 Photos: President Trump's first address to Congress US Sen. Bernie Sanders arrives for the speech. Hide Caption 22 of 22

Another national security adviser to the Trump campaign, J.D. Gordon, also disclosed Thursday that he had met with Kislyak, this time during the Republican National Convention in Cleveland in July. That meeting was first reported by USA Today

Gordon told CNN that along with national security advisers Carter Page and Walid Phares, Gordon stressed to the Russian envoy that he would like to improve relations with Russia. Gordon added that at no time did any inappropriate chatter come up about colluding with the Russians to aid the Trump campaign.

"This is not any different than anything I said publicly and on panels," Gordon said.

Phares emphatically denied meeting with Kislyak in Cleveland. "I did not meet with the Russian ambassador, though I met with many other diplomats" in Cleveland, he wrote in a blog post for the New English Review on Saturday.

In a statement to CNN, Page said he would not comment on any meetings and added that he "never did anything improper" with regard to Russia.

Page did confirm that he met with Kislyak in Cleveland, however, in an interview with MSNBC's Chris Hayes on Thursday night.

"I do not deny that," Page said.

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Gordon had advocated for language in the GOP platform that the Ukrainians not be armed in their battle against pro-Russian separatists, an effort was ultimately successful.

But Gordon says he was simply advocating what Trump himself had expressed -- that he did not wish to see major war break out over the situation in Ukraine.