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

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

Intermediate (WTI) widened slightly on Thursday:

* WCS for May delivery in Hardisty, Alberta, traded at

$11.90 a barrel below WTI, according to brokerage CalRock, after

closing at $11.75 a barrel below the benchmark on Wednesday.

* Canadian heavy crude remains close to its narrowest levels

this year after the Trans Mountain pipeline expansion project

(TMX) began commercial operations on Wednesday.

* Many analysts expect TMX will help tighten heavy crude

differentials to less than $10 a barrel below WTI by removing

export pipeline bottlenecks and forcing U.S. refiners to compete

with global buyers for Canadian barrels.

* Canada's largest oil and gas producer Canadian Natural

Resources ( CNQ ) said it is looking at opportunities to

significantly increase bitumen output at its main oil sands

mine.

* Global oil prices settled near their lowest level in seven

weeks, under pressure from weaker global demand, rising

inventories and fading hopes for a quick cut in U.S. interest

rates.