Hammers boss Slaven Bilic is an admirer of the Swede but Robertson is the priority choice and the Hammers are doing their best to get a deal across the line over the next few days.
The 22-year-old started his career at IFK Gothenburg, featuring 29 times before his switch to FC Copenhagen 18 months ago.
De factor director of football David Sullivan has seen a bid for Norwich City’s Robbie Brady fail and is focusing his efforts on Robertson – whom the club have liked for a long time – and the 22 year old Swede who has represented his country at international level on four occasions.