Mayor Bill de Blasio would not commit Thursday to appoint a new chair of the city’s embattled Housing Authority by a federally imposed deadline.

The position has been open for more than a year. The deadline is April 6.

“We’re having very productive conversations,” the mayor said of the talks between his administration and the federal government. “You know, there’s a phrase they use — I think the trains use it, I’m not sure if the planes use it — but they say, ‘on or close.’ So that’s where we are right now.”

He added: “We’re going to be on the deadline or close to the deadline. Everyone is in agreement on a solution that we can announce very soon.”

When pressed if he’d commit to hitting the deadline imposed by the city’s deal with federal regulators at the Department of Housing and Urban Development to overhaul NYCHA, he demurred.

“As I said, ‘on or close,’” he said. “What matters here is that all three parties are in agreement on the process and we’re going to be able to make an announcement soon.”