Kim Kardashian was "upset" by Kanye West's reaction to her split from Pete Davidson

A source subsequently told E! News: "Kim is upset. Not only is she sad from the breakup, but this on top of it has tested her mentally."

Kim - who has North, nine, Saint, six, Chicago, four, and Psalm, three, with Kanye - remains on good terms with Pete and she "won't tolerate"

the rap star's reaction.

The insider explained that the brunette beauty is "not okay with this type of behaviour and won't tolerate her loved ones being treated like this".

Kanye, 45, has been an outspoken critic of Pete throughout his romance with Kim - but he quickly deleted his controversial social media post following the much-discussed break-up.

Kim and Pete dated for nine months and their recent split is said to have been a "mutual decision".

An insider also insisted that a reconciliation is an unlikely prospect.

The source said: "It was an amicable split. They had discussed ending their relationship for a bit. It wasn't sudden.

"And it was a mutual decision. Getting back together is not in the cards right now."

Another source suggested that their romance had reached its natural conclusion, observing that it had been "slowing down" over recent weeks.

The insider told PEOPLE: "Things heated up quickly in the beginning when he could travel back and forth to see Kim and spend time with her, but his schedule has gotten so packed."