Abramovich was named as one of seven Russian oligarchs to have his assets frozen by the UK government due to Russia's invasion of Ukraine, with a statement calling the Chelsea owner a "prominent Russian businessman and pro-Kremlin oligarch".
A government statement said: "Abramovich is associated with a person who is or has been involved in destabilising Ukraine and undermining and threatening the territorial integrity, sovereignty and independence of Ukraine, namely Vladimir Putin, with whom Abramovich has had a close relationship for decades."
The sanctions mean Chelsea's potential sale has been put on hold, with further restrictions banning merchandise sales and tickets to non-season-ticket holders.
This news came on the same day Chelsea travelled to Norwich City for a Premier League match.
Although the Blues won 3-1 to consolidate third place in the table, midfielder Mount – who both scored and assisted goals – acknowledged the precarious situation with Abramovich had been a factor.
"You can't really avoid it, as there's a lot going on," Mount said.
"We have to focus on what we do on the pitch. We had a game today and that was the only thing we could focus on.
"We did that today, so now it's about Sunday. You try not to look too much into it."
Chelsea hosts Newcastle United on Monday (AEDT) in its first game at Stamford Bridge since these developments.