Praise be to Allaah.
This question was answered by the Standing Committee for Issuing Fatwas. The text of their reply is as follows:
After studying the matter, the Committee for issuing Fatwas replied that it is not permissible to engage in the transaction described, because it is essentially a loan with an extra amount to be paid when the loan is paid off. The form described is no more than a trick which ends up being the same as the ribaa which is forbidden by the Qur’aan and Sunnah and according to scholarly consensus. It is essential to forego dealing in such transactions, in obedience to Allaah and His Messenger (peace and blessings of Allaah be upon him).