US President Donald Trump speaks after signing the Cybersecurity and Infrastructure Security Agency Act, in the Oval Office of the White House in Washington, DC, November 16, 2018.

President Donald Trump said on Friday that he "just finished" answering the written questions posed by special counsel Robert Mueller as part of the investigation into Russian interference in the 2016 elections.

However, the president said he has not submitted his answers yet.

"You always have to be careful answering questions for people who have bad intentions," Trump told reporters Friday. The president has often criticized the Mueller probe, calling it a "witch hunt" and a "hoax."

Mueller's team is also looking into potential links between the Trump campaign and the Kremlin. The special counsel has secured guilty pleas from former Trump campaign chief Paul Manafort, former top campaign official Rick Gates and former Trump national security advisor Michael Flynn. Trump's former personal lawyer Michael Cohen, who has pleaded guilty in an unrelated case that implicates Trump in campaign finance violations, has been cooperating with Mueller, as well.

Trump on Friday also firmly denied claims that his lawyers were completing the answers for him. "My lawyers don't write answers, I write answers," he said.

The president's comments come a day after one of his personal lawyers, former New York City Mayor Rudy Giuliani, told The Washington Post that the legal team was still trying to figure out whether some of the questions would create legal problems. The Post, citing people familiar with the matter, reported Friday that Trump's lawyers believe the problem was resolved.

On Thursday, Trump sent a series of tweets condemning the investigation, calling it a "total mess." Those tweets came amid controversy over the president's firing of Attorney General Jeff Sessions and his appointing of Matthew Whitaker, a critic of the Mueller probe, as acting attorney general.

On Friday, he reiterated his criticisms, saying that the "witch hunt" has "wasted millions and millions of dollars."

"There should've never been any Mueller investigation because there was never anything done wrong," Trump said.

However, the president emphasized that he wasn't "agitated" by Mueller despite his tweets.

"I imagine it's ending now," he said of the investigation. "'I'm sure it'll be just fine."