The United States shares a 4,000 mile border with its northern neighbor, Canada. A new report by the Government Accountability Office concludes that terrorists are more likely to enter America through that stretch of land, water or air, instead of through the southern border with Mexico.

The report, titled, "Border Security: Enhanced DHS Oversight and Assessment of Interagency Coordination Is Needed for the Northern Border" concludes that the Customs and Border Protection only knew about 25 percent of all illegal border crossings up north. Further, the report states CBP was only able to make immediate arrests on 1 percent on these crossings and were limited to making arrests in just 32 miles of the expansive border.

A map included in the report represents the threats geographically. It indicates the known presence of terrorist organizations in the northwestern Blaine sector. The report also warns of possible air incursions by criminals and smigglers in the Spokane sector. The Detroit sector is vulnerable to infiltration by recreational vehicles, the report states. Finally, in the northeast, the Swanton sector should be on the lookout for criminal organizations, including terrorists.

This report was ordered by Senators Joe Lieberman, I-Conn,, Susan Collins, R-Maine, Carl Levin, D-Mich,, Daniel Akaka, D-Hawaii and Jon Tester, D-Mont. All have since expressed some form of concern about the GAO's conclusions.

President Obama and Canadian Prime Minister Stephen Harper responded Friday by outlining a new plan to increase security and trade efficiency. Their initiative was presented without many specific details, but seeks to encourage sharing more intelligence; standardizing biometrics for travelers; and coordinating systems for keeping track of people coming and going from both countries. "The goal here," Obama said, "is to make sure that we are coordinating closely and that as we are taking steps and measures to ensure both openness and security, That we are doing so in ways that enhances the relationship, as opposed to create tensions in the relationship."

Although some American and Canadian lawmakers have expressed reservations about the proposed plan to work together, because they prefer sticking to doing things their own way, and only their own way, President Obama sought to clear the air yesterday. "Canada and the U.S. are not going to match up perfectly on every measure," he said. "But we match up probably more than with any other country on earth."

Peter Doocy is currently a Washington D.C.-based correspondent for FOX News Channel (FNC).  He joined the network in 2009 as a general assignment reporter based in the New York bureau.