A bike-riding attacker with a delivery bag stabbed a pedestrian twice when they got into a spat in the middle of the street outside Washington Square Park Tuesday evening, cops and sources said.

The victim was crossing the street when he got into an argument with the suspect at Washington Square South and Thompson Street just after 5 p.m., authorities and sources said. 

The brute then knifed him in the head and back, police said. 

The victim was taken to Bellevue Hospital, where he was listed in stable condition. 

The attacker – who was riding a white bike and carrying a red delivery bag – pedaled away, heading south on Thompson Street and then east on West 3rd Street, authorities and sources said. 

No arrests had been made by Wednesday morning. 

The nature of their argument wasn’t immediately clear.

The attack came about three months after a 33-year-old man was stabbed and robbed during a clash over food inside the iconic greenspace, cops said.

The victim was on the north side of the park around 9:30 p.m. Aug. 15 when the spat erupted, authorities said. 

The assailant knifed the parkgoer in the back and then snatched his backpack, police said. 

Overall felony crime is down by nearly 14% year-to-date in the confines of the Sixth Precinct, which covers Greenwich Village and the West Village, including the park, according to the latest NYPD data.

Felony assaults, specifically, have dipped about 17% so far this year – with 152 such crimes reported, compared to 182 during the same period last year.