US Cash Crude-Grades firm on first day of September trade

July 28 (Reuters) - U.S. cash crude grades strengthened on Monday, dealers said, stabilizing from a volatile roll period on the first day of September trade.

The three-day roll trade period begins on the session after the expiration of the front-month U.S. crude futures contract CLc1. Traders use it to square positions and manage exposure.

Key grades WTI Midland rose 30 cents, while Mars Sour WTC-MRS firmed 90 cents.

The discount between U.S. crude and Brent crude oil widened to $3.34, the widest in over 10 days. A wider spread boost U.S. exports.

Oil prices rose 2% on Monday after a trade deal between the U.S. and the European Union, and U.S. President Donald Trump's announcement that he would shorten the deadline for Russia to end its war in Ukraine or face sanctions.

The U.S. and EU struck a trade deal that called for $250 billion of EU purchases of U.S. energy per year.

Meanwhile, Saudi Arabia, the world's biggest oil exporter, may hike crude oil prices for Asian buyers for the second month in a row, with September prices set to hit five-month highs on tight supply and robust demand, refining sources said.

Higher prices for crude from the country to Asia may incentivize some buyers to purchase U.S. crude.

U.S. oil refiners are expected to have about 171,000 barrels per day (bpd) of capacity offline in the week ending August 1, unchanged from the previous week, research company IIR Energy said on Monday.

* Light Louisiana Sweet WTC-LLS for August delivery weakened $1.60 at a midpoint of a $1.00 premium and was seen bid and offered between a 90-cent and $1.10 a barrel premium to U.S. crude futures

* Mars Sour WTC-MRS weakened 10 cents at a midpoint of a $1.2 discount and was seen bid and offered between a $1.30 and $1.10 discount to U.S. crude futures

* WTI Midland WTC-WTM strengthened 5 cents at a midpoint of a 10-cent premium and was seen bid and offered between parity and 20-cent premium to U.S. crude futures

* West Texas Sour WTC-WTS was little changed at a midpoint of a 70-cent discount and was seen bid and offered between a 90-cent and 50-cent discount to U.S. crude futures

* WTI at East Houston WTC-MEH, also known as MEH, traded between a 50-cent and 70-cent premium to U.S. crude futures

* ICE Brent September futures LCOc1 fell 74 cents to settle at $68.44 a barrel

* West Texas Intermediate September crude CLc1 futures fell 87 cents to settle at $65.16 a barrel

* The Brent/WTI spread WTCLc1-LCOc1 widened to last trade at minus $3.26, after hitting a high of minus $3.12 and a low of minus $3.28