London is one step closer to getting its own National Football League franchise, with Alistair Kirkwood, gridiron's UK managing director, saying that the sport's global expansion plans are steadily ticking all the right boxes.

The Jacksonville Jaguars are the latest team to make London their home away from home after signing a four-year deal which will mean they play one game a season in the English capital starting next year. Kirkwood and his NFL UK staff have helped turn the sport's International Series, which began in 2007, into a roaring success that annually sells out Wembley Stadium, and a league meeting in Houston last year voted to continue playing games in Britain until at least 2016.

"I think the first chapter has been considered a success with the owners voting on a renewal going forward," Kirkwood said. "Jacksonville returning is also a sign of maturity of the concept.

"What this now does is allow us to test if we can bring in more new fans and boost a single team recognition.

"Once that period has come up we will then have learned an awful lot about it and know what the viability for us going forward is, and then be in a great position to make a call [on a London franchise]."

The popular International Series has boosted the NFL's profile across Europe, with the inaugural game between the New York Giants and the Miami Dolphins injecting an estimated £23m into the English capital's economy, according to the London and Partners promotional organisation.

Numbers released by NFL UK also augur well for potential growth, showing there are two million British fans, and TV ratings for American football games shown on Sundays have increased by 154%.

The sixth instalment of the Wembley series will see the St Louis Rams battle last year's Super Bowl runners-up the New England Patriots on October 28, and Roger Goodell, the NFL commissioner, thinks the latest London fixture will further boost the sport's popularity..

"Part of our theory here is that London could some day be host for an NFL franchise," said Goodell. "Every time we've taken another step in exposing our game to a global audience they've wanted more. We went from pre-season games to regular-season games, and now they want more.

"We are likely to take the next step from one game a year to two games a year and maybe even beyond that."