Oct 2 (Reuters) - The discount on Western Canada Select

(WCS) heavy crude versus the North American benchmark West Texas

Intermediate (WTI) widened on Wednesday:

* WCS for November delivery in Hardisty, Alberta, settled at

$12.85 a barrel below WTI, according to brokerage CalRock,

having settled at $12.70 a barrel under the benchmark on

Tuesday.

* Suncor Energy ( SU ) said it will start two weeks of

planned maintenance at its 137,000-barrel-per-day Montreal,

Quebec, refinery on Oct. 7.

* Global oil prices edged up on worries that the escalating

conflict in the Middle East could threaten oil supplies from the

world's top producing region, but a large build in U.S. crude

inventories limited gains.