The Russian is believed to have signed off on the Serb's desire to link up with his former manager once again as a goodwill gesture given his service to the club.
This is not the first time that Abramovich has made such a gesture, in fact, he did similar back in 2015 when he allowed Petr Cech to join Arsenal contrary to then manager Jose Mourinho's wishes.
However, in this case, it is also understood that Chelsea will be adding what the media is calling a 'Lukaku tax' to any transfer fee for Matic.
The two clubs are yet to agree a fee for the 28-year-old with Chelsea understood to be wanting around £50m for the player, despite being prepared to sell the player abroad for less.
Jose Mourinho is keen to reinforce his midfield this summer and has long been linked with a move for his former player, though he will now have to pay a premium.
The Portuguese left Chelsea furious after swooping in to sign Romelu Lukaku from under their noses, hence the implementation of the 'Lukaku tax'.