The 24-year-old has signed a one-year deal at McDiarmid Park, and is the club’s second summer signing after Drey Wright arrived from Colchester United.

Watt, who has had nine previous clubs including Standard Liege and OH Leuven in Belgium, has been on Saints manager Tommy Wright’s radar for some time.

The Northern Irishman told the club’s official website: “We actually enquired about Tony last January, as well as when he was at Charlton Athletic.

“I’m delighted to finally get him here; he will add a lot to our squad and increases our attacking options.

“He’s the kind of striker that can score you a goal out of nothing and he’s hungry to get going.

“He’s still only 24 and he comes to the club with a clean slate. We want him to realise his potential here and he knows how I operate and he’s keen to be a part of it.”

Watt added that he was “itching” to get going with the Saints.

Tony Watt has joined St Johnstone on a one-year deal. Picture: SNS Group

He said: “It’s been a while since I’ve been involved and after training with the boys this morning I was really impressed with the standard. I can’t wait to get started.”

Watt shot to prominence in November 2012 when he scored Celtic’s winner against Barcelona in a Champions League tie but his career since has been nomadic.

During his last stint in Scotland - a loan spell with Hearts - he found the net just once in 17 matches, and returned to parent club Charlton at the halfway point of the season.

He found the net ten times in 56 matches during his four seasons at the Valley.

He also turned out for Blackburn Rovers and Cardiff City, scoring twice for both clubs.

Watt is expected to be involved in the St Johnstone’s pre-season friendly with Berwick Rangers tomorrow [Tuesday].

Done deal: Tony Watt signs one-year deal with St Johnstone