Roy Keane’s agent says he expects to receive a firm offer from Celtic for the Irishman’s services.

But he warned that Keane, 34, may not be prepared to take a reduction in the £90,000 a week salary he received at Manchester United.

“Roy is not yet prepared to accept he’ll have to compromise,” Michael Kennedy told the Scottish Sun.

“There has been a lot of interest in him and he has a lot to consider. Celtic have not stepped up their interest but we are expecting a call.”

Keane has admitted before that he would like to end his career at Celtic, and the club waqsted little time expressing an interest in signing Keane after his abrupt departure from Old Trafford last week.

However, Celtic have already confirmed they cannot match the wages he received at United.

“That’s a sum that’s out of the question for us,” Celtic chairman Brian Quinn told BBC Five Live on Sunday.

But speaking on Tuesday, Kennedy added: “I heard what Quinn said – but we’ll see what happens.”

Keane is not eligible to join another club until the transfer window opens on 1 January.

A number of Premiership clubs have been linked with him, with many in the Premiership confirming their interest.

Meanwhile, United manager Sir Alex Ferguson has spoken for the first time about Keane’s exit.

“Players get older,” he said. “This is the horrible part when you are manager of one club for a long time.”

“You have to make changes in a quicker fashion than other clubs can because the demands of our club are great.

“When we make decisions it is not for any other reason than to get better and to keep this club at the top. It’s always sad when a great player departs the scenes of his triumph, but football does not stand still.

“Sometimes you have to grasp the nettle. This is an occasion where we have to show what we are.”

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