Victor Wanyama is reported to have rejected an improved contract from Celtic.

Wanyama has seen his stock rise rapidly in his time in Scotland and is said to have been interesting several top-flight English clubs.

The 21-year-old Kenyan midfielder, who arrived from Belgian side Beerschot AC in the summer of 2011, is under contract with Neil Lennon's side until 2015.

Following impressive performances, Celtic have taken the proactive step of offering an improved deal to the player.

It has been reported Wanyama was offered a more lucrative package, which would also have added an additional year on to his contract.

Wanyama's agent Rob Moore, who watched his client in action against Barcelona in the Champions League on Tuesday, said that the offer from Celtic had been rejected.

''Victor has informed Celtic the contract offer fell short of his expectations," Moore said.

"There were a number of aspects that fell short – he turned it down."

Celtic boss Lennon said last week that he hoped to hold more talks with Moore and Wanyama this week, but the agent says no further discussions have taken place.

"There hasn't been another offer," Moore added. "The ball is in Celtic's court.''

Celtic rejected an offer believed to be in excess of £8million from Queens Park Rangers in the summer for Wanyama.

The player's agent says the midfielder is enjoying his football in Scotland, but is aware he could earn more elsewhere.

"He is very happy with the job he is doing at the moment. He is a great professional and his commitment cannot be questioned.

"But it doesn't take a rocket scientist to work out that he lost great earning potential in the summer (by not moving to England)."