ST. GEORGE — A long-standing boundary dispute between Washington city and St. George could wind up in court and delay progress of a new $200 million airport planned for the region.

At issue is 1,436 acres located immediately east of the St. George replacement airport site, which sits about five miles southeast of the city. The property is largely privately owned, although the Bureau of Land Management and the State Institutional Trust Lands Administration also own a significant portion of the land.

The disputed property is included in the airport vicinity land-use plan as the main entryway into the expanded 1,500-acre regional airport. St. George owns about 450 acres of the amount needed for the airport and last year received a $17.2 million grant from the Federal Aviation Administration to purchase the remaining property.

Whether that land, which now lies within an unincorporated area of Washington County, is eventually annexed into Washington city or St. George remains to be seen. Officials from each city are accusing the others of playing games and even lying when it comes down to the timing of an annexation petition by a group of landowners and passage of a state law that could affect everyone involved.

HB362, which was introduced on behalf of St. George during the waning moments of the 2007 legislative session by Rep. Steve Urquhart, R-St. George, and supported by Rep. Brad Last, R-Hurricane, gives St. George the power to approve or disapprove annexation petitions on land within a two-mile conical radius of the replacement airport site.

"We learned of the legislation once it was already under way," said Washington city Mayor Terril Clove, who sent a letter to city residents outlining his reasons for opposing the bill.

Clove wrote that the bill was represented to the Legislature and governor's office "under the pretext that Washington city was completely unwilling to work with St. George on these important land-use issues, which is untrue."

"The sole purpose of the law was to stop any current or future annexations around the airport from coming to Washington city," the mayor wrote. "The law gives unilateral veto rights to St. George city without any means of due process for Washington city."

St. George officials say they were forced to seek the bill's passage to protect the city's huge investment from "a Las Vegas developer-driven annexation petition."

"This annexation petition was surreptitiously filed a couple of days before we met with Washington city about the bill (HB362)," said St. George City Attorney Shawn Guzman. "Then when we met, they said they didn't know anything about the annexation petition.