Construction was set to begin on the 2.7-acre Pier 55 off West 13th Street on July 5. View Full Caption Pier55 Inc/Heatherwick Studio

MEATPACKING DISTRICT — Construction on a controversial $130 million island park in the Hudson River funded by Barry Diller will be delayed until at least the fall after a state appeals court slapped developers with an temporary stay to give opponents more time to prepare their case.

The New York State Appellate Division issued an injunction Thursday against the Hudson River Park project, known as Pier55, halting all construction until at least September after opponents the City Club of New York, activist Tom Fox and environmentalist Rob Buchanan sued to block the project — arguing it's wrong to use parkland for ticketed events at a proposed amphitheater on the island.

The opponents had appealed an earlier decision by Manhattan Supreme Court Judge Joan Lobis who ruled in April that their claims were "without merit" because the revenue generated from the venue would go toward maintaining the park. Lobis ruled that qualified as "a park purpose" as defined by the 1998 Hudson River Park Act that helped create the green space and requires it be financially solvent without government aid.

The appeals court granted a stay until September to allow the City Club and other advocates time to prepare their case.

City Club President Michael Gruen issued a statement hailing the injunction as a "valuable step in ensuring that this secretive and misguided project will not get off the ground."

Gruen and his allies believe the project will damage the river ecosystem.

Construction was set to begin on the park early this summer.

Gruen, Fox and Buchanan are also suing the state Department of Environmental Conservation in Albany County Supreme Court and the Army Corps of Engineers in the Southern District of New York federal court. Both entities reviewed the project and issued permits allowing it to proceed.

They lost a bid in the Southern District on Wednesday to stop the construction when the judge said they hadn't "sustained [their] burden of showing irreparable harm," but the case is ongoing.

“By continuing its misguided crusade, the City Club is obstructing the will of the local community and undermining a much-needed effort to create new public parks in New York City," said a spokesperson for the organization Diller created for the project, Pier55 Inc. "This is a temporary delay for a project that has won approval from all levels of government and consistently withstood legal scrutiny. We are committed to making Pier55 a reality and providing nearly three acres of public green space for all New Yorkers to enjoy.”

And a spokesman for the Trust called the lawsuit "time-wasting and out-of-touch," as well as "an insult not just to the local community board, which overwhelmingly supports this project, but to the New Yorkers from across the city who will enjoy this park for years to come."