Good intentions that may back fire

I help a friend (A) to make a loan from another friend (B) who loans money for a profit or interest. My friend B coursed loaned money to my current account so I can hand it over to the friend A.There was no written contract for this loan. Friend A Issued a check for the amount loaned with interest payable to CASH that I held on to to be turned over to friend B. The loan was supposed to be for one month only, so I informed B that A will not be able to pay the loan and instead will pay for one month interest. A couple of months passed and B told me that A hasn't been paying the interest and the principal for the loan and is demanding me that I should pay him for the loan that A made because I referred A to him and if wont pay-up, they will sue me. B also told me that the check that A issued will not be enough and that I should issue a check to cover the remaining balance. Can I be sued for this? And will it be a factor that B coursed the loan for A using my bank account.

no written agreement? do you have proof you gave money to a?

There was no written contract and yes I used my check to turnover the loan to A.