Donald Trump called "Morning Joe" co-hosts Joe Scarborough and Mika Brzezinski "unwatchable" on Monday in a new series of harsh tweets directed at the MSNBC duo.

Trump has been involved in Twitter feuds with in the past, but Trump got personal today when he wrote, "Some day, when things calm down, I'll tell the real story of @JoeNBC and his very insecure long-time girlfriend, @morningmika. Two clowns!"

"Tried watching low-rated @Morning_Joe this morning, unwatchable! @morningmika is off the wall, a neurotic and not very bright mess," Trump wrote.

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The "Morning Joe" co-hosts are often rumored to be romantically involved by New York tabloids, but Scarborough didn't address Trump's reference to the relationship rumor in his response.

"Thanks for watching. Morning Joe is enjoying its best ratings ever thanks to obsessed fans like you," Scarborough fired back. "Neurotic and not very bright? Look in the mirror."

Trump has a bizarre history with Scarborough and Brzezinski, who were so cozy with the GOP nominee during primary season that some people even speculated that Scarborough was angling for the vice presidential gig on Trump's ticket. "Morning Joe" took Trump serious from the day he announced, and allowed Trump to frequently call in, often lobbing him softball questions.

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Brzezinski and Scarborough were accused of turning a February MSNBC Town Hall with Trump into a "puff session" — and that was before audio leaked from a hot mic that captured the trio talking during commercial breaks.

"We really do have to go to some questions," Scarborough said during the break before Trump chimed in with, "Nothing too hard, Mika," who can then be heard saying, "OK." Brzezinski told the Huffington Post's Michael Calderone that she was talking to her producer, not Trump.

Ever since Trump won the Republican primary, Brzezinski and Scarborough have publicly turned on him. The show is essentially an anti-Trump infomercial these days, but Trump's personal attacks could destroy the relationship for good.

Some day, when things calm down, I'll tell the real story of @JoeNBC and his very insecure long-time girlfriend, @morningmika. Two clowns!

— Donald J. Trump (@realDonaldTrump) August 22, 2016

Tried watching low-rated @Morning_Joe this morning, unwatchable! @morningmika is off the wall, a neurotic and not very bright mess!

— Donald J. Trump (@realDonaldTrump) August 22, 2016

Thanks for watching.
Morning Joe is enjoying it's best ratings ever thanks to obsessed fans like you. GLAD???? https://t.co/FPaqGW9JWv

— Joe Scarborough (@JoeNBC) August 22, 2016

Neurotic and not very bright?
Look in the mirror. https://t.co/FPaqGW9JWv

— Joe Scarborough (@JoeNBC) August 22, 2016

Read original story Donald Trump Rips MSNBC's 'Morning Joe' Co-Hosts for Being 'Unwatchable' At TheWrap