Roma have given potential investor Sheik Adnan Adel Aref al Qaddumi al Shtewi until March 14 to pay for his share of the club having carried out due diligence on the deal.
It was reported last week the club had reached a 'preliminary agreement' with the Qatari but, with shares in the club rising and then sharply falling on Monday, media reports began to cast doubt on Al Qaddami's financial legitimacy.
In a statement on their website Roma claim Al Qaddami must pay the full investment, believed to be €50 million, by mid-March for the transaction to be completed. The club also confirmed Al Qaddumi's finances were being assessed while issuing the Sheik with the legal guarantees concerning financial assets at Roma.
Despite Rome prosecutors having opened a court inquiry into the deal to buy into Roma, Al Qaddumi is upbeat about his chances of investment.
The Sheik, who studied in Italy and has lived just outside Perugia for the last 25 years with his Italian wife, also revealed he was part of a consortium that tried to buy the club two years ago.
Talking to Il Tempo magazine, he said: "I've always been a big Roma fan and always intended to invest in Italy. I love this country and feel 100% Italian and want to stay here. I tried to get into the club with Acquamarcia, who proposed full acquisition of the company but my advisors and auditors advised me against buying the club."