Former US Secretary of State Hillary Clinton said she was "convinced" that there was collusion between Russia and members of Donald Trump's team during the 2016 presidential campaign, the media reported.
"There certainly was communication and there certainly was an understanding of some sort," Clinton told USA Today in an interview on Monday night about her new book, "What Happened".
"Because there's no doubt in my mind that (Russian President Vladimir) Putin wanted me to lose and wanted Trump to win. And there's no doubt in my mind that there are a tangle of financial relationships between Trump and his operation with Russian money.
"And there's no doubt in my mind that the Trump campaign and other associates have worked really hard to hide their connections with Russians."
When asked if believes there was collusion by Trump associates, Clinton said: "I'm convinced of it... I happen to believe in the rule of law and believe in evidence, so I'm not going to go off and make all kinds of outrageous claims.
"But if you look at what we've learned since (the election), it's pretty troubling."
Regarding her loss to Trump, the former First Lady said: "I'll always feel terrible that it happened, that I couldn't figure out how to counter all of the stuff that was coming at me in good enough, fast enough real time."
She told the USA Today that she accepted responsibility for the shortcomings of her campaign, faulting herself for the "bad optics" of delivering high-priced speeches and the "boneheaded mistake" when she decided to use a private email server as Secretary of State.