Reports have linked Zigic with a possible summer switch to Tyneside in a swap deal, with Magpies full-back Jose Enrique going to Valencia.
Zigic's future at Valencia looks uncertain with the giant striker failing to make an impact at La Mestalla last season.
The Serbian international has been continually linked with a move to England and the player's agent, Milan Calasan, says the big targetman would welcome a move to St James' Park.
"Yes Nikola would be interested in a move to Newcastle as he has always wanted to play in England," Calasan told Skysports.
"There are many clubs interested in Nikola including some from Italy, but we are waiting to see what Valencia want to do.
"We do not know if Valencia want to keep him or sell him."