Mobile phone network Three have requested a suspension of their sponsorship deal with Chelsea.
Three succeeded Yokohama Tyres as Chelsea's shirt sponsor in 2020, and reportedly pay the Premier League club £40million (€47.65m) a year for the privilege.
However, sanctions imposed upon Chelsea owner Roman Abramovich by the UK government mean his assets - including Chelsea - have been seized.
Chelsea have had to receive a special licence from the UK government to fulfil their fixtures, but tickets for their games cannot be sold to non-season ticket holders (ie those that have already paid for them).
The sale of the club has also been put on hold, with Abramovich paying the price for his links to Russian president Vladimir Putin.
A Three spokesperson said on Thursday, "In light of the government's recently announced sanctions, we have requested Chelsea Football Club temporarily suspend our sponsorship of the club, including the removal of our brand from shirts and around the stadium until further notice.
4/4 I know this brings some uncertainty, but the Government will work with the league & clubs to keep football being played while ensuring sanctions hit those intended. Football clubs are cultural assets and the bedrock of our communities. We're committed to protecting them.
— Nadine Dorries (@NadineDorries) March 10, 2022
"We recognise that this decision will impact the many Chelsea fans who follow their team passionately.
"However, we feel that given the circumstances, and the Government sanctions that is in place, it is the right thing to do."
Chelsea are due to take the field away to Norwich City on Thursday evening, and play host to Newcastle on Sunday.
It's been reported that Chelsea are seeking immediate talks with the UK government in a bid to secure the very existence of the club.
There are serious fears that an inability to generate revenue under the restrictions will put the club in grave danger.
Writing on Twitter earlier in the day, UK Culture Secretary Nadine Dorries said of the sanctions, "I know this brings some uncertainty, but the Government will work with the league & clubs to keep football being played while ensuring sanctions hit those intended.
"Football clubs are cultural assets and the bedrock of our communities. We're committed to protecting them."
— Off The Ball (@offtheball) March 10, 2022