The Red Devils are one of a number of clubs keeping tabs on Norway international Haaland, who has scored 39 goals in 41 appearances for Borussia Dortmund.
‘If I’m Manchester United, I’m doing all I can to buy Harry Kane,’ he told Sky Sports.
‘I know Erling Haaland is on a lot of radars, but there should be only one person on Man Utd’s radar: Harry Kane.
‘If they want to close the gap to Man City, they need someone to come to that club and score goals the minute he walks into that club, like Harry Kane can.
‘Because Kane has done it, year in, year out, in this relentless league. Who is to know Haaland is going to hit the ground running in this league?
‘You don’t have time in this league. Timo Werner was scoring goals left, right and centre, but came here and has struggled.
‘Sometimes I watch Kane and think: “Am I the only one who sees this?” I’d be paying everything to sign him. He’s got the entire package.
‘Manchester United need to win the league now, not in five or six years’ time.
‘Don’t get me wrong, Haaland is an unbelievable prospect. But for me it’s a no brainer – I’d want to win the league now!’
Ole Gunnar Solskjaer’s Manchester United climbed to the top of the Premier League last month but a poor run of form has seen them slip seven points behind leaders Man City, who also have a game in hand.
Merson can also see Pep Guardiola’s City targeting Kane, adding: ‘I wouldn’t be surprised if Man City went for him, but that depends on how they do in the Champions League.
‘The only thing that’s going to stop them winning the competition is missed chances. If it is down to missed chances, I know who I want in my team next year: Harry Kane.
‘But I’ll say it again: his family may be happy where they are. A lot of things at Tottenham tick his boxes, but he won’t want too many days like he had on Saturday.’
Kane has established himself as one of the most prolific goalscorers in world football at Tottenham but is yet to win any silverware.
And Merson believes he may need to leave north London to win trophies and break Alan Shearer’s all-time Premier League goals record.
He said: ‘I thought after the game on Saturday [Man City 3-0 Tottenham], “I wonder how Harry Kane feels when he gets home?”
‘He’s going to be 28 in the summer – his next three years will be his best years. He’s got a big thing to weigh up now
‘I don’t think he gets near Alan Shearer’s record (260 Premier League goals to Kane’s 156) at Tottenham playing this way. Far from it.
‘I said at the start of the season he’ll have a big decision. When you have a game like that against City, and he knows his football because he’s an intelligent player, he will know Spurs are a million miles off Man City. A million miles.’
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