The Washington Monument will remain closed for at least the next two-and-a-half years, the US National Park Service says.
The 170-metre tower was shut down on August 17 following repeated problems with the structure's elevator.
Financier and philanthropist David Rubinstein has agreed to provide up to US$3 million (NZ$4.18 million) for a major upgrade to the elevator, having earlier donated US$7.5m (NZ$10.45m) to repair the damage done to the monument by a 2011 earthquake.
But while the funding for the overhaul is secured, there is no date set for the start of the work, according to The Washington Post.
The Park Service is awaiting congressional approval of funding for a new security screening facility at the site, a project officials want to carry out at the same time as the improvements to the elevator, the Post said.
