Bernie Sanders says he's still not endorsing Hillary Clinton but it's not because he harbors 'hate' for her, as Donald Trump has claimed.

Sanders, who hasn't quit the race, said Thursday he's still working with the Clinton campaign and isn't at a point yet where he can go before his supporters and discuss her stances on key issues.

'I do not hate Secretary Clinton,' Sanders told MSNBC's Chris Hayes. 'We have disagreements on issues, but to say that I hate her is absolutely untrue.'

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Bernie Sanders, seen here today in Vermont, says he is not endorsing Hillary Clinton, contrary to a claim from Vice President Joe Biden that one is on its way

'I talked to Joe, I think, was three weeks ago,' Sanders told MSNBC host Chris Hayes, referencing his meeting with his old Senate colleague at the vice president's residence the day President Barack Obama formally endorsed Clinton

Trump said this week at a rally in Maine that Sanders secretly despises Clinton.

'He'll be nasty and say, "Oh, I'd never vote for Trump," but that's OK. I know what he thinks inside,' Trump proclaimed.

The Republican said, 'He hates her. He hates her.'

'I mean, he cannot stand her,' Trump stated.

Vice President Joe Biden told NPR Thursday that his former Senate colleague was actually on the cusp of endorsing his primary rival.

The NPR interview has yet to air, but the radio outlet said yesterday on its Twitter account that Biden said, 'I've talked to Bernie. Bernie is going to endorse her. This is going to work out.'

'I talked to Joe, I think, was three weeks ago,' Sanders said MSNBC, referencing his meeting with Biden at the vice president's residence the day President Barack Obama formally endorsed Clinton.

Speaking to Hayes about an endorsement, Sanders said, 'Look, on that issue, we are trying to work with Secretary Clinton's campaign on areas that we can agree on.'

The MSNBC host asked the progressive senator felt he'd ever be in a position to endorse Clinton, if that's the case.

Sanders asserted then, as he has repeatedly since the final primary, 'I'm going to do everything I can to defeat Donald Trump.'

Hayes tried to get the losing Democrat to to be more definitive, probing him as to whether that statement includes appearing at rallies with Clinton and participating in other campaign activities.

However, the Vermont senator wouldn't commit just yet.

'We are working with the Clinton campaign, trying to be able to come forward to my supporters and say: "You know what, here's the progress we have made, here's what Secretary Clinton is saying on this issue and that issue." '

Sanders, who hasn't quit the race, said he's still working with the Clinton campaign and isn't at a point yet where he can go before his supporters and discuss her stances on key issues. That doesn't mean that he harbors 'hate' for her, though, Sanders said, a claim that Donald Trump has made

Sanders is no longer campaigning for the presidency and has acknowledged that Clinton will be the Democratic Party nominee.

He continues to linger in the race without a formal withdraw while the party considers the platform it will present at the convention.

Representatives from both campaigns and the Democratic National Committee will meet in Orlando, Florida, next week for a final round of talks before the party convention.

Democrats will officially name Clinton as their nominee at the convention in Philadelphia at the end of July.