Liverpool have confirmed that Adam Lallana has signed a new "long-term contract" with the club.

The 28-year-old has been in fine form so far this season, scoring seven goals in 21 Premier League appearances to establish himself as a key part of Jurgen Klopp's plans.

The exact length of the contract has not been disclosed by the club, but it is understood to be a three-year deal worth £110,000 a week, with the option of an additional 12 months at the end of it.

"I'm very proud and feel quite humbled by the show of faith from the club and the manager in particular. Signing for a club like Liverpool is obviously a big thing – but to re-sign shows you've obviously contributed enough that the people who make the decisions want you to stay longer," Lallana told the club's official website.

"This is a really good place to be at the moment and, for a player who wants to be part of something special, I can't think of a better club to commit your future to. We have a brilliant squad of players who are only going to get better the longer we are together. We have a world-class manager and coaching staff.

"And because it's Liverpool there is that added X-factor of the supporters and what success would mean to them when we achieve it here. I'm just delighted that I'm going to be part of it for even longer. I would say I feel in this moment like I'm playing as well as I ever have – and if that is the case of course the next challenge is to maintain or improve.

"That is always the case at a club like this – you have to keep proving yourself and challenging yourself. I think my best years are still ahead of me because I feel so fresh and confident. You can't always promise to be the best player on the pitch but I think you can promise to try your best each and every game. I try to do that and I think the Liverpool supporters see that in me."

Lallana has scored 20 goals in 117 appearances for Liverpool since joining from Southampton in 2014.