"We are using solar panels. As you know, India had donated that, and we're very appreciative for the donation," he said at a daily briefing on Monday.
Haq was answering a reporter's question if the solar panels given by India were being used and if they would power escalators that have been shut down in the UN's austerity drive.
"The issue with the escalators, as we pointed out, is an issue having to do with our budget," Haq said.
"When it comes to our cost-cutting measures, we'll keep reviewing them and probably bring more services online once the money comes in," he added.
Facing a cash crunch because some countries, including the US that is the UN's biggest contributor, have not paid all their dues, the world body introduced austerity measures on October 14.
These included symbolic measures like turning off the fountain in front of the UN headquarters and the escalators.
Closing some UN facilities early, restrictions on travel and reducing translation and multilingual interpretation were among more substantiative measures.
The escalator service was turned on to some floors earlier this month, but not to the two used by the media and staffers. Those on those floors have to use the lifts or the fire escape staircases.
A suggestion was made last week to use the power from the solar park inaugurated by Prime Minister Narendra Modi in September to power the escalators as the power from it is free and outside the budget.
The solar park on the roof of a building in the headquarters complex has a capacity of 50 kilowatts.
It was donated by India to commemorate the 150 birth anniversary of Mahatma Gandhi and to underline New Delhi's commitment to fighting climate change.
(Arul Louis can be contacted at arul.l@.in and followed on Twitter @arulouis)
( With inputs from IANS )