Petrov, 26, submitted a transfer request towards the end of last season, which was immediately rejected by Celtic chiefs.

The Bulgarian is reported to be increasingly frustrated at the prospect of spending the new term at Parkhead.

But, so far, the only concrete offer has been from Portsmouth whose bid of £3.5m (€5m) fell well short of Celtic’s valuation of the midfielder.

Lennon believes Petrov is good enough to realise his dream of playing for one of the top five clubs in the Barclays Premiership one day.

But he has urged his team-mate not to throw away Champions League football, and the chance of another SPL championship medal, for a move south of the border he may regret.

“We all hope that he decides to stay,” said Lennon. “But, at the minute, his mind seems to be made up.

“I spoke to him at the end of May and his ambition is to play in England.

“It would be a massive loss for us if he went so I’m sure the club are doing all that they can to keep him.

“It’s got to be a big club, really, because there is still a lot going on here, it’s a huge club.

“If you did leave this club you would miss it unless you went to one of the top four or five clubs in England.

“I have played in England myself and I know the Premiership and I know the standard of this club as well.

“Allied to that, we have the Champions League to look forward to and there’s a good buzz about the club at the minute.

“He is taking a gamble, and giving up a lot, but that’s his prerogative.”

Lennon is well aware that manager Gordon Strachan would struggle to find a suitable replacement for Petrov on the funds he has at his disposal.

He added: “In this day and age, a goalscoring midfielder is priceless.

“But it’s not just his goals that he gives us, it’s his all round game. He has blossomed into a fantastic player.

“It will cost us a hell of a lot of money to replace someone like that.

“He has grown up here at the club and, to be fair, it has been his life for the last six or seven years and I can understand he might want a fresh start in England.

“But I am sure he understands why we all want him to stay.”

Lennon has committed his own future to Celtic by agreeing a one year deal, despite the offer of a longer contract and a coaching role at Crystal Palace.

The Northern Irishman, 35, was tempted by the opportunity to join Peter Taylor at Palace.

But with so much to look forward to next season, he opted to stay.

“It would have been really hard for me to leave the club at this stage in my career,” said Lennon.

“I still think I have a lot to offer and, after speaking to the manager, he thinks so as well.

“They always said they wanted me to stay and these things just take a bit of time.

“People were on holiday and then I was on holiday so it was really only when I got back that we got down to sorting it out and I got to speak to the manager.

“After I had spoken to him, it was all done and dusted really.”

Speaking of the interest from Palace, he added: “It was a very good offer. I knew Peter from my days at Leicester and he was very good to me.

“He has done very well at his previous clubs and it was a wee bit tempting.

“But I have still got a lot to play for up here. If I left Celtic now, at such an exciting stage, I thought I might regret it later on down the line.

“It was always my first intention to try to get something resolved here and I’m delighted that I did.”