Newcastle United intend to reward Alexander Isak for another sensational season with a new long-term contract in the summer and remain adamant the striker is not for sale at any price.

Isak scored another two goals against Southampton, winning and converting the penalty that earned Newcastle an equaliser, before a sublime first touch and ice-cold finish put the visitors in front.

The Sweden international caused havoc all afternoon and could have had a second hat-trick of the campaign.

His scintillating performance underlined how important the 25-year-old is to Eddie Howe’s side and the Newcastle hierarchy are determined to ensure they keep him long-term.

Talks about extending a deal that still has three-and-a-half years left to run were paused last year, but Telegraph Sport can reveal that negotiations for a new contract are pencilled in to begin at the end of the season, when there are no games to worry about as a distraction.

Isak has repeatedly said he is happy and settled on Tyneside. Any new deal would recognise his status at the club by making him their highest-paid player.