Another former Trump campaign aide has changed his plea to guilty.

Rick Gates' admission of conspiracy and lying to FBI investigators means he's willing to co-operate and testify against others.

This comes as special counsel Robert Mueller has revealed the latest charges against former Trump aide, Paul Manafort.

He's accused of secretly paying unnamed European politicians in 2012 and 2013 to lobby for Ukraine's then government, which was pro-Moscow.

Court papers say Manafort also wired the politicians more than two million euros ($2.5m).

Al Jazeera's Patty Culhane reports from Washington, DC.