Construction on a new playground in Union Square Park can move forward, but a judge has stalled the renovation of the pavilion on the north end to accommodate a restaurant.

Justice Jane Solomon of New York State Supreme Court, New York County, yesterday extended indefinitely a week-long temporary restraining order against construction on the pavilion.

The plaintiffs in the case, which include local residents and community groups, say the pavilion should not be used as a seasonal restaurant, as has been suggested by planners, but should be devoted to playground space. They argue in their suit that the state Legislature should have to approve the use of the park as a restaurant before it goes forward.

City officials have responded to complaints by noting that the $21 million plan would triple the current playground space in the park.

A city attorney, Chris Reo, said yesterday in a statement that he was pleased that, as part of the court decision, construction on the new playground area could go forward while the pavilion issue is debated.

“We are confident in the City’s legal position, and hopeful that, upon reviewing the papers, the Court will agree that this project should immediately proceed,” Mr. Reo said.