Williams shone against Leeds in the World Club Challenge

The 19-year-old New Zealand loose forward is out of contract at the end of the season and Wigan are rumoured to be leading the chase for his signature.

"A couple of English clubs have registered their interest and one has put a figure on paper," said Chris Orr, part of Williams' management company.

"The size of the offer blew us away and the Bulldogs increased their offer (of a new contract) considerably."

Orr would neither confirm or deny whether Wigan was one of the clubs to have shown an interest.

Farrell in union talks

However, the Warriors are believed to have earmarked Williams as a possible replacement for Andy Farrell, who is likely to switch to rugby union.

Wigan coach Denis Betts admitted his club were interested in Williams but was coy when asked about their chances of getting him.

"It would be nice, wouldn't it? Can he get here next week?" Betts said.

"Everyone is going to talk about Sonny and I'm sure Leeds, Wigan and all the big clubs will be interested.

"If a player of that quality becomes available, then you would have to say, 'Please consider us'."

However, Williams would prefer to stay in Australia.

"It's about Sonny Bill getting a package that reflects his status," Orr said.

"There are offers from England and obviously there are going to be other NRL clubs that will be very interested if they get the chance.

"He wants to make sure he is able to look after himself and his family back home, but at the same time the Bulldogs are very important to him."