Trump's former campaign chairman Paul Manafort has been accused of lying to the Federal Bureau of Investigation in violation of his plea agreement, Manafort refutes the allegation, and elusive "Russian collusion" still nowhere in sight.
Manafort denies that he lied, and his attorneys say he believes he "provided truthful information".
Manafort said in the same filing he disagreed with Special Counsel Robert Mueller's assertion that he lied to investigators.
He was convicted in a Virginia federal court on eight counts of financial fraud. Earlier this month, there were mounting tensions between Mueller and Manafort over Manafort's apparent lack of cooperation with the investigation, multiple sources familiar with the matter told ABC News. It'll be up to U.S. District Judge Amy Berman Jackson to decide whether that's the case, after taking into consideration Manafort's claim that in many meetings with the government, he didn't lie.
The intervention means Mr Manafort could potentially face bank fraud charges, which were dismissed as part of the plea bargain.More news: United States police fire tear gas at migrants trying to cross from Mexico
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The surprise development came at a critical time for Mueller, who is expected to finalise a report in the coming months on the findings of his 18-month probe into Russia's election meddling and possible collusion between Moscow and the Trump campaign.
Both the special counsel and Manafort's attorneys agreed there was no reason to delay his sentencing and asked the court to set a date for that. The president's first national security adviser, Michael Flynn, entered into a plea deal with Mueller, while Trump's longtime personal lawyer, Michael Cohen, has been providing information to Mueller's team and federal prosecutors in NY, among others, a person familiar with the matter has said.
The charges only relate to Manafort's political consulting with pro-Russian politicians in Ukraine, largely pre-dating his role with the Trump campaign.
The apparent collapse of Manafort's cooperation agreement is the latest stunning turnaround in his case, exposing the longtime Republican consultant to more than a decade behind bars after pleading guilty in September on charges of cheating the Internal Revenue Service (IRS), violating foreign lobbying laws and attempting to obstruct justice. He attended a meeting at Trump Tower in June 2016 with a group of Russians offering "dirt" on Democratic candidate Hillary Clinton, who lost in an upset to Trump in the presidential vote that November. Prosecutors said Gates, who also pleaded guilty, is cooperating in "several ongoing investigations".