UPDATE: Two window cleaners rescued after nerve-wracking 90 minutes dangling outside 68th floor of One World Trade Center

Two window cleaners have been rescued after dangling on a scaffold stranded outside the 68^th floor of the One World Trade Center in New York.

Rescuers cut a panel out of a window near the scaffolding and pulled the cleaners through after a nerve-wracking 90 minutes.

The platform the workers were on collapsed just before 1pm local time, according to the Office of Emergency Management, leaving the cleaners stranded near the 68th floor.

NYPD officers were lowered in a second scaffolding to try to secure the workers.

However, the police scaffolding was raised back to the top of the building soon afterward, without reaching the trapped window cleaners.

It took rescuers some time to carefully cut through the panel of fortified outer glass to get to the workers.

Initial reports say the victims were done cleaning and were about to ascend to the top of the tower when the cable that pulls the scaffold up became loose.

The workers are uninjured and in good condition.

The 104-storey skyscraper is the US’ tallest building.