Andy Warhol's iconic Shot Sage Blue Marilyn sold at Christie's auction in New York for $307 million

One of the world's most expensive portraits has fetched NZ$307 million at auction in New York.

The late Andy Warhol's iconic 1964 pop art portrait of legendary film star Marilyn Monroe is a fixture of pop culture. Her star power is still as far-reaching as it was over half a century ago. 

After a frenzy of international high-stakes bidding at New York's Rockefeller Centre on Tuesday (NZ time), Warhol's iconic artwork got an anonymous new owner. 

"At $170 million, for the Warhol, selling here, to you sir, $170 million," the auctioneer said as he finalised the deal, congratulating the anonymous bidder sitting in the crowd. 

The post-auction price the buyer will pay is US$195 million - about $NZ307 million - going down as the most expensive piece of American artwork ever sold. 

It didn't quite match the record-shattering US$450 million paid in 2017 for the Jesus-depicted 'Salvator Mundi', said to be painted by Renaissance painter Leonardo da Vinci, purchased by a buyer reportedly on behalf of Saudi Arabia's Crown Prince Mohammed bin Salman.

The price tag may be eye-watering, but rest assured that all proceeds will go to charity, a dying wish from the late Swiss art collector-turned-philanthropist, Doris Ammann. She and her brother Thomas were two of the most respected art dealers in the world.

Warhol's portrait, named 'Shot Sage Blue Marilyn', earned its curious title after a performance artist infamously shot at his Marilyn Monroe paintings with a revolver shortly after creation. 

But the art piece's fame mostly comes from its subject whose legend lives on. Her 1962 Golden Globes gown was donned by reality TV personality Kim Kardashian at this month's Met Gala. 

Monroe - real name Norma Jeane - is clearly still just as recognisable today as she ever was.