The two banks are understood to have been in more detailed talks with the sponsors since shortly after they were shortlisted for the mandate in mid-May, along with rivals HSBC and SABB.

Although sources close to the situation had already confirmed that RBS and Riyad had won the mandate, it had not been officially confirmed until now (MEED 25:06:08).

The project, being developed by Aramco and US-based Dow Chemical Company, is likely to split up into a number of smaller projects to break the financing requirements down into more manageable sizes, according to bankers in the region.