The 19-year-old has already played six Tests, 19 one-day internationals and 10 T20 matches for his country, taking 54 wickets in the shorter formats.

Director of cricket Giles White told BBC Radio Solent Shaheen was the "best death bowler we could possibly find".

"He's quick, he's about 6ft 6ins tall, he gets bounce, he has good skills and is extremely accurate," White said.

"And add to that his variations and you have a really good package.

"You look at the shorter format of the game and it's the bowlers who influence games more often that not. If you have a world-class bowling attack you generally do very well in this competition.

"We have had that in the past and Shaheen fits the bill and fits in very well with the other bowlers we have got. He's an emerging young talent in world cricket and we are delighted to have him on board."

Next season's T20 Blast competition sees the group stages begin on Thursday, 28 May and run until Sunday, 12 July. The quarter-finals are scheduled for mid-August with Finals Day at Edgbaston on Saturday, 5 August.

White says the fact Pakistan are touring England next summer means Shaheen should be available for the entire tournament but it is "always a changing landscape".

He added: "His availability looks good as it leads into a Test series in England afterwards so it fits us very well.

"Hopefully he is a player that plays for us a for quite a long time and we forge a long-term relationship with him."