West Ham United co-owner David Sullivan has rubbished Sporting Lisbon's communications chief Nuno Saraiva's claims that the Irons never submitted a bid for midfielder William Carvalho and insists Slaven Bilic's side made an offer for the Portugal international.

Saraiva responded to Sullivan's recent comments about the Hammers' pursuit of Carvalho by calling him a "liar" and a "parasite" and stressed that Sporting received no offer for their esteemed midfielder, who has attracted plenty of interest from Premier League clubs in recent seasons.

A rather astonishing Facebook post from Saraiva read: "David Sullivan lies. At Sporting Clube de Portugal, as has already been said by our president, no proposal was made for our player William Carvalho.

"The football industry is not the set of an adult film in which all obscenities are allowed. So the boss of a club demands a lot more than this intellectual pornography."

"Mr David Sullivan has a duty to prove what he says. That is why Sporting Clube de Portugal challenges him to publicly show the proposals he claims to have been made as well as the evidence that Sporting CP received them.

"One thing is certain: Sporting CP, as has already been said, does not cut the legs off its players. But we have nothing to do with the performance of entrepreneurs or relatives who live at the expense of players and who are offering them to clubs as if they were cheap supermarket merchandise.

"It creates regrettable situations that have already forced the sporting club of Portugal to take drastic measures to defend itself from these characters who parasitize the lives of some players."

Sullivan was quick to defend himself, insisting that West Ham's bid for Carvalho was submitted to Sporting via the player's agent and their Portuguese representatives but the club's president Bruno de Carvalho did not want the public to know of Sporting's willingness to sell one of their prized assets.

The 68-year-old also said that the troubled Irons submitted a written bid, while his David Sullivan Junior branded Saraiva's statement as "serious libel" in a brief Twitter post.

"They are NOT TRUE!" Sullivan told West Ham fanzine Claret and Hugh.

"But he (Bruno de Carvalho) can't admit publicly that he was prepared to sell him. Our bid was submitted via the player's agent and our negotiators in Portugal. We also put in a written bid."

Reports suggested that West Ham were prepared to offer £31m for Carvalho, valued at €40m by Sporting, but a deal never materialised despite Sullivan claiming that Sporting eventually accepted their original proposal.

The whole sorry episode comes at a rather bleak time for West Ham, who currently lie at the bottom of the Premier League table with no points from their first three games. Their woeful start to the season has led to concerns over the future of Bilic, who may be relieved of his duties if his side fail to get a decent result at home to Huddersfield Town after the international break.

David Sullivan
Sullivan has quickly responded to Saraiva's claims.Getty Images