Michael Flynn was charged with "willfully and knowingly" making "false, fictitious and fraudulent statements" regarding his meeting with the Russian ambassador to the US, according to court documents.

Prosecutors say Mr Flynn was directed by “a very senior” member of President Trump’s transition team to speak with Sergey Kislyak, a conversation in which the pair discussed US sanctions on Moscow.

The former advisor is accused of falsely claiming that he did not ask the Russian ambassador to "refrain from escalating the situation in response to sanctions that the United States had imposed against Russia that same day".

And he also claimed not to remember the ambassador telling him that Russia had "chosen to moderate its response to those sanctions as a result of his request".

Mr Flynn pled guilty to the charge at a court hearing this morning after turning himself in to authorities.

Following the court hearing, a statement from Mr Flynn confirmed he was cooperating special counsel Robert Mueller's investigation in to possible links between the Trump campaign and Russia.

The statement said his cooperation was in the best interest of his family and the United States.

Mr Flynn said he recognised his actions were wrong, but that it had been “painful to ensure false accusations of treason and other outrageous acts”. 

A sentencing hearing is expected to be held in around three months. 

He also stands accused of filing false statements and omitting details about his company’s work with the Turkish government. 

Flynn is at the centre of a broader investigation by special counsel Robert Mueller into links between the Trump campaign and Russian operatives.

It had appeared that Mueller’s team was seeking a deal of some kind to win Flynn’s cooperation in that investigation.

And his plea suggests the retired three-star general is now cooperating with the team of Special Counsel Robert Mueller.

Mr Flynn resigned from his post in February, just a month after former business tycoon Trump came into office.

At the time he denied accusations that he discussed sanctions with the Russian ambassador to the US before Trump became President.

The former army general has still has not disclosed what was discussed in his conversations with Sergey Kislyak yet in his resignation letter he admitted he misled Mike Pence.

Michael Flynn issued a resignation letter following the scandal.

His letter read: “In the course of my duties as the incoming National Security Advisor, I held numerous phone calls with foreign counterparts, ministers, and ambassadors.

“These calls were to facilitate a smooth transition and begin to build the necessary relationships between the President, his advisers and foreign leaders. Such calls are standard practice in any transition of this magnitude.

“Unfortunately, because of the fast pace of events, I inadvertently briefed the Vice President Elect and others with incomplete information regarding my phone calls with the Russian Ambassador.

“I have sincerely apologised to the president and the Vice President, and they have accepted my apology.”

Flynn admitted he first met Sergey Kislyak in 2013 and held several conversations with Russia’s Ambassador to the US more than once before Trump’s inauguration.

One of the calls took place on the same day Obama hit Moscow with sanctions.

A Trump administration official confirmed the White House was aware of the warning.