Liverpool’s £15m man out for the rest of the season
Boss Brendan Rogers and Allen himself had been hoping that they could put off the surgery until mid-April but the club decided to take action now during the international break.
Allen withdrew from the Wales squad who face Scotland and Croatia in the crucial World Cup Qualifiers.
He will now have surgery on the shoulder that has been affecting him since Autumn and will be out for three months to recover, meaning the midfielder should be back for pre-season training in July.
The Welshman secured a transfer to Anfield at the start of the season for a fee of around £15million.
He has made 27 appearances for the club, but after making a bright start to life for The Kop his form dipped dramatically and has found himself in a battle to break into the first team squad, especially after the return of Brazilian Lucas from injury.