Slaven Bilic remains undeterred in his pursuit of Sunderland striker Jermain Defoe despite West Ham having a reported £6 million bid rejected.

Only five teams have scored fewer than West Ham's return of 23 Premier League goals this season, with winger Michail Antonio shouldering much of the burden with eight goals.

Andy Carroll - who has spent most of the season injured - is the highest-scoring of their recognised strikers with just two goals, while Simone Zaza, Ashley Fletcher, Diafra Sakho and Jonathan Calleri have only two between them.

By contrast, former Hammers striker Defoe has been a rare positive for relegation-threatened Sunderland this term, scoring 11 of their 19 Premier League goals as they desperately look to fend off relegation.

And Bilic, who initially refused to speak about other clubs' players, lavished praise on the 34-year-old after seemingly confirming West Ham have made a move to bring him back to the club.

"It [news of the bid] was on television," Bilic told reporters. "But we're not going to discuss players that are not ours.

"The whole club is trying really hard to get some players in positions that we need. But I'm not going to talk here in public.

"He has the things that are most important in a football game and that's goals. Last season he was probably the main reason Sunderland stayed up and he has continued to play the same way this season.

"Each game he is not only scoring goals but creating chances and most of the chances he's converting into goals."

Bilic also confirmed reports that he had been keeping an eye on Brentford's 24-year-old striker Scott Hogan, who has 14 Championship goals to his name this term.

"He's a good player," he added. "I've watched him a few times. Again he is scoring goals, he's very sharp, very quick and a very good finisher.

"He does it in the Championship. But once again, Hogan is not on our roster."

West Ham's need for offensive reinforcements has been made even more urgent by speculation linking Zaza with a departure and Bilic has acknowledged the Italian is nearing the exit door.

"We wanted him at West Ham and he wanted to come, but because of his contract I can say his story with us is finished," Bilic said.

"He is still our player until the moment he goes somewhere but mainly it's the circumstance with his contract. He's definitely a good player and we had big expectations but it just wasn't to be."