Tonev, 23, has 11 caps for Bulgaria's senior international side and is also a reported target for Fiorentina and Lazio, but regular Champions League football could give Celtic the edge.

The winger still has a contract until June 2015, but it has been suggested that the Polish side are looking for two million pounds and the player would welcome a move.

"It's an honour to know Celtic are interested in me," the Bulgarian said. "They have a big history and their performance in Europe this year has shown they are ready to create some new history.

"Last summer there were Italian teams interested and even though Serie A is one of the top leagues it's important for me to consistently play Champions League football. Celtic is somewhere I could achieve that.

"I just concentrate on playing. Hopefully a move can be organised this summer."