Arsenal’s hugely experienced centre-back Sol Campbell has emerged as a target, while the club continues to pursue Fulham midfielder Luis Boa Morte among others after chairman Freddy Shepherd insisted a top-six finish is a must.

“If we get the players in that we are targeting, I am cool with that,” Souness said. “I can live with that but if – and that is a big word, if – we get the players in we are talking about bringing in because at the end of the day, it would not take a mathematician to work out that we are short of numbers at this time at Newcastle.

“We have sold six; we have got two in. We have got two cracking players in Scott Parker and Emre, but we need, in my opinion, another three top men and maybe another two to be squad players.

"If we are to compete with the big boys, we need three more top men – when I say top men, established players who have been very good players either playing in the Premiership or have experience in the Premiership – and I would like two more that could come in and be squad players.

“That would cost good money, but we have targets and we will have to go and get them because we are short, and if we do that, I am more than confident if we can avoid a run of injuries to our top players, we can have a really good season next year.”

The arrival of Turkish international Emre as the club braced itself for an approach from Arsenal for Jermaine Jenas, ended a lengthy pursuit and rewarded the Magpies for their persistence.

The 24-year-old left-sided midfielder, who will wear the number five shirt vacated by central defender Andy O’Brien when he moved to Portsmouth, is relishing the chance to test himself in the Barclays Premiership after his spell in Serie A.

“I am very happy to have signed for Newcastle United because they are one of the biggest clubs in England,” he said.

“This is a very big club and I am so excited about the prospect of playing in the Premiership. It is a new challenge and one I am looking forward to very much.

“I would like to thank the manager Graeme Souness and chairman Freddy Shepherd for having the trust in me to bring me to Newcastle. Now I will give my very best for Newcastle and try to bring success to the club.”

Emre is no stranger to St James’ Park having played there in a 4-1 Champions League victory for Inter in November 2002.

“I remember that night very well,” he told the club’s official website, www.nufc.co.uk. “St James’ Park is a fantastic stadium and the fans make a wonderful atmosphere inside the ground. I am looking forward to playing there many times as a Newcastle player now.”