The United States and Canada have preliminarily agreed that American personnel may inspect Buffalo-bound trucks in Fort Erie, Ont., as part of a long- sought plan to improve traffic flow across the Peace Bridge.

Sen. Charles E. Schumer, D-N.Y., announced the pilot agreement Monday after yearlong negotiations involving the U.S. Department of Homeland Security and its Canadian counterpart.

The plan calls for the Peace Bridge to serve as one of two experimental border crossings for 18 months beginning in late December, though the details of allowing armed Immigration and Customs Enforcement and Customs and Border Protection officers to operate in Canada – a major sticking point in previous negotiations – have yet to be determined.

Still, sources close to the talks say the two governments have agreed to one of two options. One involves allowing U.S. law enforcement officers to carry guns on Canadian soil but be subject to stringent Canadian laws and regulations. The sources say that plan could receive tough scrutiny from the officers’ union.

Another option would allow armed Canadian law enforcement personnel to accompany U.S. officers during inspections in Fort Erie, similar to current U.S. operations at major Canadian airports, including Pearson International in Toronto. Either way, the sources say Homeland Security Secretary Janet Napolitano has assured negotiators the plan is virtually certain to be implemented.

The pilot program will initially involve only the Peace Bridge and another international crossing that sources say is located in the State of Washington, with an eye toward a permanent arrangement that will require the approval of Congress and Parliament. The Washington State program is expected to begin first, followed by the larger scale effort on the Peace Bridge.

Homeland Security spokesman Peter Boogaard said initiation of the pilot program requires a bilateral memorandum of understanding expected to be completed soon by Homeland Security and Public Safety Canada, working with Customs and Border Protection and the Canada Border Services Agency.

“[Homeland Security] does not anticipate any obstacles preventing completion of the MOU in short order,” he said.

Schumer said the move will not only expedite traffic across the international span but boost trade and tourism, too.

“Now that the pilot program is in place, I will continue to work hard to ensure that the program has all the resources it needs to be successful, so that preclearance can become permanent down the road for Peace Bridge motorists,” he said. “The announcement of the pilot program is a two-way victory for Western New York and Canadian businesses.”

Eliminating the truck bottleneck on the Peace Bridge has proved an elusive goal for many years. Local officials have always expressed interest in how such a “preclearance” arrangement on the Canadian side of the Niagara River could ease long lines on the bridge and eliminate idling trucks on the current Buffalo plaza.

The issue also becomes especially important as the Peace Bridge Authority looks to soon build a new inspections plaza on the U.S. side.

Schumer said Monday the latest development will allow the authority to consider all sorts of design options for the Buffalo plaza.

“By doing inspections on the Canadian side, it gives the people designing the New York side far more flexibility,” he said Monday, adding that much more room for inspecting trucks is available in Fort Erie.

Gov. Andrew M. Cuomo and Rep. Brian Higgins, D-Buffalo, also have been active in seeking the program for Buffalo and Fort Erie.

Cuomo said in July that placing the preclearance program in Fort Erie would represent an “early win” for the “Beyond the Border” agreement announced last year by President Obama and Canadian Prime Minister Stephen Harper, designed to further encourage trade between the nations.

Napolitano said in February 2011 that obstacles surrounding the question of armed U.S. personnel in Canada would prevent any preclearance agreement. “It cannot be done,” she said.

But Schumer and other U.S. officials refused to let the issue die, leading Washington hearings on the subject, meeting with Canadian Ambassador Gary Doer and speaking by telephone with Foreign Minister John Baird and Minister of Public Safety Vic Towes.

Schumer said that in order for the pilot program to be become permanent, it must prove successful in expediting traffic, trade and tourism between the United States and Canada, with no adverse impact on security.

He said Congress and Parliament must then pass laws that permanently govern the “privileges and immunities” of U.S. and Canadian personnel connected with the program.

Once the U.S. and Canadian governments agree to language on a permanent framework, Schumer said, he assured Homeland Security and the Canadian government that he will spearhead the effort for passage of permanent legislation in the Senate.