Is it permissible to impose penalty clauses on those who are late in paying their deferred installments, knowing that the selling price differs between cash and deferred payments?

It is impermissible to impose penalty clauses on those who delay in paying due installments, because it is explicit usury (riba), resembling the dealings of the people of Jahiliyyah (pre-Islamic ignorance). Despite the harm inflicted upon companies and banks by procrastinating debtors, specialists have not yet issued a new legal fatwa (definition) to solve this problem. It is advised to deal with trustworthy individuals or to use available guarantees such as checks or mortgages to preserve rights.