RIYADH (Reuters) - Some members of Saudi Arabia's ruling family and business elite have expressed frustration with Crown Prince Mohammed bin Salman's leadership following the biggest attack on the kingdom's oil infrastructure last month, Reuters reported.

The news agency quoted a senior foreign diplomat and five sources with ties to the royal family and business elite - all of whom asked not to be named - that this raised concern among a number of prominent branches of the powerful family of Saud about the ability of the crown prince to defend the largest exporter Of the world's oil and its leadership.

The sources said the attack sparked outrage among some who believe in elite circles that the crown prince sought to tighten his grip on power. Some said the attack had drawn criticism among those who believed it had taken an overly aggressive attitude toward Iran.

One source, a member of the Saudi elite with ties to the royal family, said: "How could they not be able to monitor the attack?"

He added that some members of the elite say they "do not trust" the crown prince, as confirmed by the other four sources and the senior diplomat.