For the week commencing 5 March, refinery margins primarily weakened across each of the key refining regions due to a rise in product stock levels. Weekly stock levels for gasoline, middle distillates and residual fuel oil in the US, NW Europe, Japan, Singapore and the Middle East are expected to have rebuilt to a four-week high. This is primarily due to a large build of fuel oil in both NW Europe and at Fujairah. The price of all regional crude oil benchmarks weakened last week, with Dated Brent softening by just over US$0.50/bbl. But Urals crude in the Med was under particular pressure, meaning the Brent-Urals Med differential moved to its widest level since 2011, due to refinery maintenance and ample supply of competing grades. US domestic crude prices were also under pressure, with the seventh consecutive stock build on the US Gulf Coast amid imports and refinery maintenance. The Brent-WTI and Brent-LLS differentials were relatively flat on the previous week.