Sens. Cory Booker (D-N.J.) and Kirsten Gillibrand (D-N.Y.) on Wednesday came out in favor of starting an impeachment inquiry into President Donald Trump , a stronger position than either 2020 presidential hopeful has taken thus far.

Gillibrand released a statement Wednesday afternoon saying that she also now believes it is time to start impeachment hearings:

From the beginning, I have called for a proper process in order to secure key testimony and information related to the Mueller investigation, so that Congress ― as a co-equal branch of government ― can fulfill its responsibility to deliver the truth to the American people. But the White House has repeatedly stonewalled Congress’ ability to take basic fact-finding steps and make an informed decision. Combined with the fact that Robert Mueller clearly expects Congress to exercise its constitutional authority and take steps that he could not, it’s time for Republicans and Democrats to begin impeachment hearings and follow the facts wherever they may lead. We cannot let this president defy basic accountability measures built into our Constitution.

On Wednesday, special counsel Robert Mueller gave his first public comments on the findings from his investigation into Russia’s interference, and the Trump campaign’s cooperation, in the 2016 U.S. elections.

Mueller said he didn’t have the legal authority to charge Trump with a crime ― but that doesn’t necessarily mean Trump is innocent.

“As set forth in the report, after that investigation, if we had had confidence that the president clearly did not commit a crime, we would have said so,” Mueller said.

Mueller also strongly hinted that it’s now Congress’ job to do something, saying the Constitution “requires a process other than the criminal justice system to formally accuse a sitting president of wrongdoing.”

Mueller had made similar comments in the report, most of which was released publicly, but both Booker and Gillibrand had stopped short of calling for impeachment proceedings.

With their remarks Wednesday, Booker and Gillibrand join other 2020 Democratic presidential contenders, including Sen. Elizabeth Warren (Mass.), Sen. Kamala Harris (Calif.), former Rep. Beto O’Rourke (Texas) and former Housing and Urban Development Secretary Julian Castro, in calling for impeachment proceedings.

But other candidates still aren’t quite sold. Joe Biden’s campaign said Wednesday that while impeachment may become “unavoidable if this Administration continues on its path,” the former vice president isn’t quite there yet.

“Vice President Biden will continue to make the case as to why President Trump should not be re-elected. That is the surefire way to get him out of office,” his campaign said.

South Bend, Indiana, Mayor Pete Buttigieg said Mueller’s comments were “as close to an impeachment referral as it gets” ― but he didn’t say he personally supports Congress pursuing impeachment.

In an interview with HuffPost while campaigning in Iowa over Memorial Day weekend, Booker had said he was inching toward calling for impeachment after reading the full Mueller report.

“Everybody should be outraged. We can’t slip so far into tribalism that we lose our ability to say ‘this is wrong, if not illegal.’ And Mueller himself points to 10 things that speak to obstruction of justice. There are things in that Mueller report that are indications of criminal activity,” Booker said while riding in a campaign RV between two stops in southeast Iowa. “The Congress of the United States of America, by constitutional design, should continue this investigation. And that shouldn’t be complicated.”

He went on to suggest that the Trump administration’s obstruction of Congress’ investigation could be grounds for impeachment.

“Everything now is on the table, from legal challenges to impeachment proceedings,” Booker said. “We’re seeing a situation where the president isn’t allowing our work to get done. That’s very serious, that a president is trying to stop what Congress should do when you have a report in your hands like that. And when a president is going to do that, you should look at other options that you have, whether it’s elevating it to impeachment proceedings or using contingent court battles.”

This piece has been updated throughout.

CORRECTION: An earlier version of this piece referred to Pete Buttigieg as the former mayor of South Bend, Indiana. He is the current mayor.