Kris Commons says Celtic urgently need to find a top-quality striker to compliment their midfielders.
West Ham boss Sam Allardyce claims he knows nothing about any possible move for Obafemi Martins.
Internacional have insisted there have still been no offers for Leandro Damiao, following fresh speculation suggesting Southampton had entered the race for his signature.
Tottenham Hotspur have been linked with a move for the Brazilian striker for some time but have yet to make an official bid.
Recent reports claimed that Southampton were also keen on the 23-year-old and were plotting a big-money swoop, but Internacional maintain there is no deal imminent.
Director of football Luis Cesar Souto de Moura admits there has been interest, but he is hopeful that Damiao will not be going anywhere.
"Nothing has come, clubs from everywhere sound him out all the time, but we don't even consider that anymore, as there are too many enquiries but offers never come," he told 'Esporte Interativo.
"I am working with the idea of keeping the player, so that he doesn't leave."