Crisis club Newcastle United are bracing themselves for another blow with shirt sponsors Wonga contemplating ending their sponsorship, just as they have done at Blackpool and Hearts.

The controversial payday loan company agreed a £24m deal with Newcastle in 2012. However, the move caused outcry, with Tyneside MPs criticising the deal. Now the club, who could be relegated to the Championship on Sunday, face the possibility the contract may not be renewed.

The uncertainty about which division Newcastle will play in next season and the massive difference in financial rewards between the Premier League and the Championship have meant that all major decisions – new head coach, player recruitment and potential new sponsors – have been put on hold until Sunday.

John Irving, the club’s finance director, has already resigned and will leave his position to move to Newcastle International Airport in the summer. There will be an end-of-season review, in which the managing director, Lee Charnley, will face questions about what has gone so dramatically wrong.

Newcastle’s new home strip for next season, which was released on Tuesday, will not feature the new Wonga logo, following a rebranding at the payday lenders.

The sponsorship deal Wonga signed with Newcastle runs until 2017. In the final year of that deal, Newcastle’s shirts for children will not feature Wonga branding at all. The company revealed losses of £40m on Monday, along with job cuts. They have ended their sponsorship deals with Hearts and Blackpool. Newcastle are expected to be next.

Wonga declined to comment on Thursday night but said a decision had not yet been made.