Tottenham are considering a state-of-the-art stadium with a retractable pitch that enables them to become the home of a new NFL London franchise.

The bold design of the new £400million stadium, due to be completed for the start of the 2018-19 season, could involve a ‘slide-out’ grass football pitch with an NFL-style synthetic surface housed underneath.

The option of extra-large changing rooms, to accommodate NFL squad sizes that can amount to as many as 70 players at a game, is also being explored by architects.

Tottenham are considering sharing their new £400m stadium with an NFL franchise

A spokesman for the north London club did not rule out the possibility this week, confirming that they are ‘looking at options’ in order to ‘future-proof the design’.

The NFL is said to be within five years of having a permanent franchise in London. Indeed officials will be testing logistics when they stage their three games at Wembley this autumn, with teams looking at how quickly they can have their players back in the USA and ready to play again.

The clash between the Buffalo Bills and Jacksonville Jaguars on October 25 will kick-off at 1.30pm while the New York Jets vs Miami Dolphins game on October 4 and Detroit Lions vs Kansas City Chiefs contest on November 1 will both begin at 2.30pm.

As well as allowing the NFL to experiment with a live game on TV at breakfast time in the States (9.30am Eastern time), teams are able to take advantage of the time difference and be home on American soil by Sunday night.

Tottenham's new state-of-the-art stadium is due to be ready in time for the 2018-19 season

Spurs' new 65,000 capacity stadium could be better suited to the NFL than the 90,000-seat Wembley

If Tottenham press ahead with the proposed stadium design and secure the NFL franchise it would represent a significant blow to the FA, who also see the NFL as a potentially lucrative partner for Wembley, their £757m stadium.

But the NFL are keeping their options open at this stage in the knowledge that a new London stadium designed with American football requirements in mind would be hugely advantageous.

Even the proposed capacity of 65,000 for the new White Hart Lane is a more realistic target than 90,000 seats which Wembley boasts.

Wembley does have the iconic status that the NFL finds attractive but there are other issues with the national stadium. Not least the fact that they have to leave the lowest 5,000 seats empty so that the view of spectators is not restricted by the mass of huge bodies on the touchline.

The modern NFL stadiums make sight-lines for spectators a priority and the new White Hart Lane could overcome the problem that is experienced at Wembley by having the artificial pitch at a significantly lower level beneath the moveable grass pitch.

Wembley has hosted NFL regular-season matches since the International Series began in 2007

Detroit Lions' clash with Atlanta Falcons kicked off early, as will all three games at Wembley later this year

Retractable grass pitches are nothing new in modern stadia design. England have played on two: at Gelsenkirchen in Germany during the 2006 World Cup and in the Sapporo Dome in Japan four years earlier.

The Gelredome in Holland also has a retractable pitch, as does the University of Phoenix Stadium that hosted this year’s Super Bowl.

The advantage for these stadiums is the ability to grow the grass in a more natural environment, outside, away from the shadows of the stands while also having the capacity to stage different events without damaging the playing surface.

A feat of modern engineering, a pitch can be moved outside the stadium in less than four hours.