Stuart Armstrong has signed a new contract with Celtic, committing to the club until the summer of 2019.

The midfielder's existing contract was due to expire at the end of this season and Armstrong had been linked with a cut-price move to England if a new deal was not agreed.

Celtic boss Brendan Rodgers had suggested delays over agreeing the new deal had affected Armstrong's performances recently but continued talks with the player's advisers have been successful.

Armstrong, who has been at Celtic since February 2015, was a key player in the club's treble-winning season and enjoyed a sharp upturn in form under Rodgers.

"I am delighted to sign this new contract with Celtic," Armstrong told the club's official website.

"I have had a tremendous time at the club so far and it has been a period in my footballing career which I have enjoyed immensely.

"It has been an honour to play for a club of such stature. I have enjoyed a great relationship with our supporters and we have achieved a high level of success, something it has been great to be part of."

He added: "I'm pleased that this new contract has been agreed and I am now looking forward very much to working with the manager, our staff and my teammates to bring the club and our fans even more success."