Sam Allardyce has managed to steer the east London club up to 10th place in their first season back in the Premier League, with a finish in the top half of the table within reach.
The Hammers are keen to make Andy Carroll’s loan move from Liverpool a permanent one and have also been linked with a swoop for Stoke City striker Peter Crouch.
And Sullivan has assured Allardyce that funds will be made available as the club look to cement their place in the English top flight.
“Our planning has already started to make sure next season is even better than this one,” Sullivan is quoted as saying by talkSPORT.
“A crucial factor of that will be recruiting the right players in the right positions.
“Our aim for the coming season is to bring in four or five players that will strengthen the squad and provide Sam Allardyce with greater options and variety next season.
“We will be aiming to bring in at least one proven goal-scorer to further bolster our attacking threat.”
Allardyce’s West Ham travel to Everton in their next Premier League game on Sunday.
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