The long-beleaguered Chicago Spire project appears to be dead.

All that’s left is the big hole in the ground where what was to be Chicago’s tallest building was to rise.

Developers Garrett Kelleher and Steve Ivankovich did not meet a court-ordered Friday deadline to pay off creditors and “bring the Chicago Spire out of bankruptcy,” according to a letter Friday from the developers’ attorney to two city officials that says the land at 400 N. Lake Shore Dr. will revert to creditor Related Midwest.

“Any bridge loan does not seem likely at this point, and, without an extension, equally unlikely, the property will revert to Related, who bought the first mortgage from the Irish government,” attorney Tom Murphy wrote to Deputy Mayor Steve Koch and to Andrew Mooney,  commissioner of the city Department of Planning and Development.

Murphy did not respond to requests for comment Saturday night.

A Related Midwest spokeswoman declined to comment.

A city spokeswoman could not be reached late Saturday.

Kelleher, the Irish founder of Shelbourne Development Group, and Ivankovich, of Chicago-based Atlas Apartment Holdings LLC, had until Friday — Oct. 31 — to pay Related Midwest $109 million, according to bankruptcy court records. The only way around that was if they were granted an extension until March 31, 2015, court records show.

Related Midwest, which reportedly acquired $93 million in debt from the failed project from Ireland’s National Asset Management Agency, filed for involuntary Chapter 11 bankruptcy last year.

“Unfortunately, the building appears to be dead now,” said Bob O’Neill, president of the Grant Park Conservancy, an advocacy group that was pushing to fix up a riverfront park as part of the Spire development. “It is a big loss because it was going to be a really internationally-visible building of 150 stories.”

Renowned Spanish architect Santiago Calatrava designed the Spire, which was to be a tapered tower with a seemingly twirling profile.

Calatrava also created a design for DuSable Park, a public park that’s now little more than weeds that’s adjacent to the coveted Spire location, O’Neill said. The Spire developers had planned to donate $9.6 million to fix up the park, which “has been languishing right at the mouth of the Chicago River … for almost 30 years,” O’Neill said.

“Now, you have a big ugly hole in the ground where the Spire site is,” O’Neill said. “And DuSable Park … is going to sit there as a pile of weeds.”