By Dominic Toner

West Ham have made an improved bid for Norwich defender Martin Olsson, according to a report.

Sky Sports claimed that the Canaries rejected a £3million bid for the Swedish defender on Monday.

The Mail Online report that West Ham have now offered £4million for the 28-year-old left-back as they look to cover for the injured Aaron Cresswell.

Cresswell picked up a knee injury in pre-season against Germain side Karlsruher and will be on the sidelines for up to four months.

He was a key player last year in an outstanding season for West Ham, who defied the odds to finish seventh in the Premier League and guarantee European football for this campaign.

Slaven Bilic is keen to secure a left-back signing in time for the opening day of the Premier League season in just under two weeks time against Chelsea.

Full-back Sam Byram was moved away from his preferred right side to fill the problem position on the left side of the defence against Domzale last Thursday in the club’s Europa League tie, while Michail Antonio also moved out of his favourite attacking midfield position to slot in at right-back.

Olsson has just 12 months remaining on his Norwich deal.

He made 28 appearances last season, scoring one goal and providing two assists from his full-back position, but he was unable to keep the club in the Premier League.

In other West Ham transfer news, they are lining up a £7million bid for a prolific attacker.