Dele Alli
Dele Alli (R) has completed his move to Tottenham from MK Dons, but will remain on-loan with the League One club for the rest of the season Richard Heathcote/Getty Images

Tottenham have completed the signing of MK Dons midfielder Dele Alli on a five-and-a-half year contract keeping him at the club until the summer of 2020.

"The young midfielder has joined us on a five-and-a-half year contract until 2020 and has now been loaned back to MK Dons for the remainder of the League One campaign," a statement on Spurs' official site read.

The north London club have beaten stiff competition from Premier League rivals Newcastle United and Liverpool in the race to bag the midfielder, who has been impressive for the Dons this campaign.

The 18-year-old has played a key role for the club this season and has already scored 12 goals in 27 appearances. The youngster enhanced his reputation as a key player in the future, when he played a starring role in MK Dons' 4-0 victory over Manchester United in the Capital One Cup earlier in the season.

Alli has expressed his delight at joining the White Hart Lane outfit and has expressed his desire to play in the front of the Spurs fans at the Lane, while admitting that he is willing to fight for a place in the team following his return from his loan spell at his former club.

"It's a massive club and I'm really happy to be here. I'm looking forward to meeting all the lads and getting to work with the manager. It's a dream come true," Alli told Spurs' official site.

"I'd love to play for Spurs and play at White Hart Lane. It won't be easy and I'll have to fight for my place in the team, but I'll work hard to do that."

Meanwhile, Tottenham have cancelled defender Benoit Assou-Ekotto's contract, which was set to expire in June. The defender has not played for the club since May 2013 and was also unimpressive during his loan spell with Queens Park Rangers last season.

"We can confirm that Benoit Assou-Ekotto has been released from his contract with the Club. We wish Benoit well for the future," Spurs confirmed on their official site.