The Blues have already accepted bids from all three clubs for the 27-year-old which is believed to be around £250,000.
A Forest spokesman said: "We tabled the same offer as Leeds and Coventry and Birmingham accepted it. We have also met Stern's personal terms,
"He has been away on international duty this week and we're expecting the situation to develop when he returns."
The Trinidad and Tobago forward averaged around a goal every four games during his previous stay at The City Ground. He was sold on the cheap after a clause in his contract meant Forest would have to pay former club Columbus Crew a significant amount if he scored another goal in our colours.
John is currently well down the pecking order at St. Andrews behind the likes of Clinton Morrison, Emile Heskey, Mikael Forssell and Dwight Yorke.
It's believed that SJ would prefer to stay in the Midlands which would put Coventry and Forest in the lead for his signature. Coventry are looking to bolster squad numbers and add to their impressive start to the Coca-Cola Championship following the departure of Callum Davenport to Spurs for £3.5m.