West Bromwich Albion's sponsor, Zoopla, has told the club to drop Nicolas Anelka over his quenelle gesture or risk their lucrative shirt deal being scrapped.

Meanwhile the club have called on the Football Association to bring a swift end to its investigation into the striker's controversial goal celebration.

According to Marketing Week, the property and house prices website company has contacted West Brom to voice its dissatisfaction following Anelka's actions, which some say carry antisemitic overtones.

Zoopla, owned by the Jewish businessman Alex Chesterman, said Anelka must be dropped for Monday's Premier League home game against Everton and has told the club it will want its name removed from the team's shirts immediately if he plays.

Zoopla is understood to have been left stunned by the decision to keep Anelka in the team while the FA investigation continues. The 34-year-old has featured in every league game since the gesture against West Ham in December, though West Brom have claimed they are powerless to act until the FA concludes its inquiry.

The FA has made no comment other than to state an independent expert is aiding its investigation and there would be no further update until 20 January at the earliest.

Immediately after the incident West Brom said in a statement that "Nicolas is eligible for matches whilst the FA carries out its investigation. Therefore, Nicolas will remain under consideration for first-team selection whilst the FA and club continue their enquiries."

From West Brom's perspective, the club are anxious to know whether Anelka will be charged with making an antisemitic gesture. If he is found guilty he could be banned for a minimum of five games under new anti-racism rules, ruling him out until March.

With the club having sold the striker Shane Long to Hull for a fee that could rise to £7m, the loss of Anelka would further weaken the new head coach Pepe Mel's forward options and undermine West Brom's struggle to stay in the top flight.

The club's sporting and technical director, Richard Garlick, said: "There are investigations ongoing and, while they are, we won't comment."

Pressed on the matter, Garlick added: "People can speculate there is a turn of events where we might be two strikers down. It would help everyone for that investigation to be over as soon as possible and the FA have given their statement about how quickly they will do that."

Anelka has confirmed that by placing his left arm across his chest while keeping his right arm pointed downwards, he was recreating the quenelle but claimed it was a "special dedication to my comedian friend Dieudonné".

Dieudonné M'Bala M'Bala, however, is well known in France for maintaining antisemitic views and for having come up with the gesture, which he first used in 2009, while standing in the European elections for an anti-Zionist party.