Former Premier League midfielder Lee Hendrie has told The Transfer Tavern in an exclusive interview that Celtic must spend more than £15m this summer if they are to reclaim their Scottish Premiership title.

Last summer, as per Transfermarkt, the Glasgow club spent around £14m on signings and loans, bringing in the likes of Albian Ajeti from West Ham and Shane Duffy from Brighton.

It was an unsuccessful season, however, for the two recruits and Celtic's other additions, with the Bhoys finishing second in the league and a whopping 25 points behind their fierce rivals.

And now Hendrie has warned that significant investment will be needed if it is to be another story next term.

Speaking exclusively to TT about what Celtic have to do this summer, the Sky Sports pundit said:

"I feel that they're going to have to spend probably a lot more than 10 or £15m to start competing with the likes of Rangers.

"Celtic is in a rebuild structure, for me. It's been proven this season that Rangers have really blew them out of the water. So your 10 and £15m is not going to cut it I don't feel.

"They're going to have to certainly recruit good loan players and certainly going to have to spend way over £15m if they're going to compete with Rangers."

It remains to be seen what sort of transfer budget Celtic's new manager will have to work with. But after the campaign they have had, and with such an influential figure like Scott Brown leaving the club, reinforcements are needed.