* Urals MED weakens, margins narrow
* Iraq to switch to ASCI from U.S. crude futures
* March BTC/Azeri steady to higher
LONDON, Feb 11 (Reuters) - Russian Urals crude oil differentials weakened in the south on Thursday as refining margins narrowed alongside firmer outright prices.
Iraq will from April switch the benchmark for pricing sales of around half a million barrels per day (bpd) of crude to the United States, a senior Iraqi oil official said on Thursday.
It will use the Argus Sour Crude Index instead of the NYMEX U.S. light sweet crude futures. Saudi Arabia and Kuwait have already switched. [ID:nWEB9729]
* Glencore bought a Urals from Vitol at dated minus 90 cents, traders said. The loading dates were thought to be Feb. 24-28. Eni bought a cargo from Gunvor at dated minus 75 cents.
Both of those were down from Wednesday, when the Feb. 20-24 period was bid to dated minus 70 cents.
* Once again there was little in the way of bids and offers, although Gunvor was offering Feb. 26-March 2 at dated minus 55 cents, in line with Wednesday, traders said.
Some traders saw better prospects to ship Urals out of the region as supportive. No bid was seen on Thursday.
* There was talk that Statoil moved its March 3 cargo of BTC at around dated plus $1.60, although that could not be confirmed. If done, that would put levels in the middle of the dated plus $1.50 to plus $1.70 heard on Wednesday.
REFINING MARGINS <REF/MARGIN1>
* Urals margins for complex refineries in the Mediterranean weakened to $2.85 a barrel, down from the five-day average of $4.00.
For a database of oil supply and demand fundamentals upstream and downstream, Reuters subscribers can click here (Reporting by Alex Lawler; Editing by Keiron Henderson)