SEOUL — South Korean opposition party leader Lee Jae-myung, who was stabbed in the neck, is recovering well but still needs close monitoring to avoid complications, a Seoul National University Hospital doctor said on Thursday (Jan 4).

Mr Lee was surrounded by journalists in the southern port city of Busan on Tuesday when a man pretending to be a supporter pushed through the crowd and lunged at him, stabbing him on the left side of his neck with a knife.

Mr Lee, who suffered a wound to his jugular vein, was first taken to a hospital in Busan, then flown to the capital Seoul where he underwent a nearly two-hour surgery. 

Mr Lee "is fortunately recovering well", said Dr Min Seung-kee, who performed the surgery.

Mr Lee had suffered a "1.4cm pierced wound that cut through his muscle", Dr Min said at a press conference, adding that "bouts of bleeding were found" in his neck.

The knife "cut about 60 per cent of the internal jugular vein", the surgeon said.

"But fortunately there were no signs of damage for artery, cerebral nerve, throat or airway."

While Mr Lee is in recovery, close monitoring is still needed, Dr Min said, as there could be complications from the wound. 

The briefing on Thursday, the first by the Seoul hospital since Mr Lee's surgery, follows the party leader's transfer from the intensive care unit to the general ward on Wednesday.

Mr Lee's Democratic Party has said he could have been killed if the assailant's knife had struck his artery, rather than his vein, calling it "pure fortune".

A court in Busan will on Thursday review an arrest warrant filed by the prosecution for the 66-year-old suspect in the stabbing, identified only by his surname Kim, on charges of attempted murder, according to the Yonhap news agency.

The warrant would allow police to continue to hold the suspect, who was arrested at the scene.

According to Yonhap, suspect Kim had been working as a real estate agent in South Chungcheong province, around 115km south of Seoul.

Citing delivery messages for registered mail from banks at his office, among other materials, Yonhap reported Kim was facing financial difficulties and had been unable to pay rent for his office for seven months. AFP