Most Asian markets turned lower for a second day Thursday, with energy firms struggling after another sell-off in oil fuelled by concerns about a planned output cut.

Crude prices are slumbering at three-month lows after OPEC member Iraq and non-member Russia suggested this week they would not take part in any limitations, despite a painful global supply glut.

Their comments have raised questions about the viability of last month's agreement by oil cartel OPEC to reduce output, that had sent prices soaring.

While edging up slightly Thursday, both main contracts have tumbled more than three percent this week and news that US stockpiles had fallen more than expected last week was unable to provide much support.

"Iraqi demands to join the list of countries exempted from quotas have simply added to the uncertainty" that an output cut can be implemented, Research firm Capital Economics said in a commentary.

"We have long been sceptical of the chances of a game-changing deal and continue to forecast that both Brent and WTI will end the year back at around $45 per barrel."

Regional energy firms extended recent losses. Hong Kong-listed CNOOC sank 2.7 percent, with traders also selling on the back of a weak earnings report.

PetroChina lost two percent in Hong Kong, while Sydney-listed Woodside Petroleum was 1.5 percent off and Santos lost two percent.

- Samsung profits dive -

Among regional markets Tokyo ended down 0.3 percent after closing Wednesday at a six-month high.

Japanese IT firm Fujitsu was the stand-out performer, soaring almost eight percent on news it was in talks to merge its struggling PC unit with Chinese computer giant Lenovo. 

Shanghai closed down 0.1 percent, Sydney slipped 1.2 percent and Hong Kong shed 0.8 percent -- extending a one percent loss Wednesday.

Seoul, however, added 0.5 percent, boosted by a pick-up in market heavyweight Samsung Electronics.

The firm confirmed a 30 percent plunge in third-quarter operating profit linked to its Galaxy Note 7 crisis but later announced its heir apparent JY Lee had joined the board, putting him a step towards control of the family-run conglomerate.

Lee Chaiwon, chief investment officer at Korea Value Asset Management said JY's bigger role should provide a much-needed boost to the beleaguered company, saying it "will become more market-friendly and will "quicken its restructuring process".

The dollar rose against its main peers and other high-yielding currencies as a preliminary survey showing the key US services sector expanded in October reinforced expectations the Federal Reserve will lift interest rates before the end of the year.

- Key figures around 0800 GMT -

Tokyo - Nikkei 225: DOWN 0.3 percent at 17,336.42 (close)

Hong Kong - Hang Seng: DOWN 0.8 percent at 23132.35 (close)

Shanghai - Composite: DOWN 0.1 percent at 3,112.35 (close)

London - FTSE 100: DOWN 0.3 percent at 6,937.68

Euro/dollar: DOWN to $1.0913 from $1.0907 Wednesday

Dollar/yen: UP to 104.67 yen from 104.51 yen

Pound/dollar: DOWN to $1.2214 from $1.2242 

Euro/pound: UP to 89.35 pence from 89.09 pence

Oil - West Texas Intermediate: Flat at $49.18 a barrel

Oil - Brent North Sea: Up five cents at $50.03

New York - Dow: UP 0.2 percent to 18,199.33 (close)

Source: AFP