SEATTLE (AP) — The International Longshore and Warehouse Union says it intends to appeal a judge’s ruling that threw out their lawsuit aimed at undoing a deal to build a new professional basketball and hockey arena in Seattle — a key part of plans to bring the NBA back to town.

The ILWU says it will announce appeal plans during a news conference. The ILWU Local 19, representing workers at the Port of Seattle, says they believe the court failed to acknowledge that the memorandum of understanding between investor Chris Hansen, the city of Seattle and King County is in violation of the state environmental protection act.

On Feb. 22, King County Superior Court Judge Douglass North held that the agreement on the proposed new arena does not violate state environmental law and while it provided a framework did not commit the city and county to building the arena south of downtown.

Copyright 2013 The Associated Press.