[buttmunch]

Stammering, gangly Hugh Grant never struck us as the sort of bloke who'd get physical with the paparazzi. But the actor has joined Sean Penn, Alec Baldwin, Chris Martin and Cameron Diaz in the proud pantheon of celebs who've lashed out at intrusive lensmen.

The "Four Weddings and a Funeral" star was obviously in no mood for impromptu portraiture yesterday when a photog spotted him walking down Central Park South around 9:20 a.m.

"Hugh Grant had his head down, looking at his cell phone, when this young guy started flashing his camera," says former Daily News spokesman Ken Frydman, who happened to witness the encounter.

Grant responded by taking the photographer's picture with his cell phone camera.

"How do you like it, mate?" an angry Grant asked the paparazzo, who continued snapping away.

Getting more fed up, Grant called the photographer "a pussy," and proceeded to hit him upside the head with a manila folder, Frydman tells us.

"The photographer kept smirking at him," says Frydman. "He said, 'I don't know what you're so mad about.'"

"You're invading my privacy," said Grant, pronouncing "privacy" in the British fashion.

"This is your last warning, you c—," Grant said.

Frydman says, "The photographer kept taunting him. That's when Grant kicked him in the butt. Not hard — he was just trying to shove him away."

Frydman, who was watching with his Source Communications partner Richard Schwartz, decided to tried to bring his public-relations expertise to bear.

"I said to the photographer, 'Leave him alone or he's going to hit you again,'" recalls Frydman. "I said to Hugh Grant, 'Don't hit him again, or he's going to sue you.'"

When last seen, Grant was marching down the street with the photographer still clicking furiously.

"I tried to mediate," shrugs Frydman. "I failed miserably."

nypost.com