Saudi Saad Group's credit problems will affect the way ratings agency Moody's assesses privately held firms across the Gulf region due to weaknesses in the operating environment, a senior analyst said.

Privately held Saad Group, part of a $30.6 billion network of firms, sent shockwaves through the Gulf last week, saying it would restructure its debt after it ran into unspecified difficulties and the Saudi central bank froze the accounts of its billionaire chairman Maan al-Sanea.

Philipp Lotter, senior vice president at Moody's, said Saad's troubles and the lack of transparency exhibited by the firm revealed much about business conditions in the Gulf.

"The operating environment here in the region is a lot less stable and predictable than we thought it was, and that has implications for credit stability," he told Reuters.

"It will affect the way we assess certain companies operating in this environment."    

Moody's last week downgraded its ratings on Saad by six notches to junk and then one day later withdrew its ratings altogether, saying it lacked enough information about the group to continue.

Likewise, Standard & Poors last week cut its ratings to default status and then withdrew coverage due to a lack of information from management.

Saad said it had appointed business law firm Lawrence Graham to work with BDO Capital Finance, whose appointment was announced last week to restructure its obligations and those at its Bahrain-based unit, Awal Bank. - Reuters