Last month, sources familiar with Cohen's legal problems told CBS News that he is increasingly feeling isolated from Mr. Trump and his allies, and Cohen appears to be moving closer to a legal strategy of cooperating with investigators given the gulf that now exists between him and Mr. Trump.
A source said about Cohen, "the signals are crystal clear" that they are turning on him.
Cohen was Mr. Trump's self-described fixer and a key player in the Trump Organization for more than a decade. His home, office and hotel room were raided in April as part of a probe by federal prosecutors in New York into his personal business dealings.
Investigators are also looking into a $130,000 payment made as part of a confidentiality agreement with porn actress Stormy Daniels, who alleges she had an affair with Mr. Trump in 2006, which Mr. Trump denies.
Cohen in the past has said that payment was made on his own initiative. But in the ABC interview, he said he couldn't comment on advice of his lawyer.
"I want to answer. One day I will answer," he said.
Cohen repeated previous denials that he had any involvement with Russian attempts to interfere with the 2016 presidential election, but he refused to criticize the investigation led by former FBI Director Robert Mueller.
"I don't like the term witch hunt," Cohen was quoted as saying.
"As an American, I repudiate Russia's or any other foreign government's attempt to interfere or meddle in our democratic process, and I would call on all Americans to do the same," Cohen said, adding that he has not been interviewed by Mueller's team.
Cohen also told ABC he did not agree with President Trump's recent tweet repeating Vladimir Putin's claim that Russia did not interfere in the election.
"Simply accepting the denial of Mr. Putin is unsustainable," Cohen said. "I respect our nation's intelligence agencies'... unanimous conclusions."
Stephanopoulos said he asked Cohen if he had any regrets about how he has handled any of the matters under investigation.
"As an attorney and as an employee, I tried to make good faith judgments in the past. I also acknowledge that I am not perfect. I would prefer not to be in this situation at all, obviously."
"I want to regain my name and my reputation and my life back," he said.