Last checked at 
(Sharecast News) - Energy giant Shell flagged fourth-quarter impairments of up to $4.5bn on Monday, primarily in its chemicals and products division.
The oil major, updating on fourth-quarter trading, said non-cash post-tax impairments were expected to be between $2.5bn and $4.5bn.
The bulk of the impairments - $1.5bn to $2.1bn - are in its chemicals and products business.
Shell said the impairments were driven primarily by macro and external developments, as well as portfolio choices. These include its Singapore chemicals and product assets, which Shell is currently looking to sell.
However, trading and optimisation in Shell's integrated gas division was expected to be "significantly" higher than the previous three months, boosted by seasonality as well as increased optimisation opportunities.
It is forecasting production of between 880,000 and 920,000 barrels of oil equivalent per day (boe/d) in the division for the quarter.
In its upstream unit, production is forecast to be between 1.83m and 1.93m boe/d.
Shell announced a strategic review of its energy and chemicals assets in Singapore last summer, as it looks to increase shareholder value and cut emissions.
The blue chip is due to publish fourth-quarter results on 1 February.
