United States President Barack Obama and his Canadian counterpart Justin Trudeau have announced an expansion of customs pre-clearance locations in Canada.As part of plans to improve travel links, America-bound passengers travelling through the Billy Bishop Toronto City Airport, Quebec City's Jean Lesage Airport and Montreal's central train station will soon be able to clear customs in Canada.In total, eight Canadian airports and Vancouver's Pacific Central train station already have U.S. Customs and Border Protection pre-clearance facilities that allow passengers to skip traditional border stops when entering the U.S.The pre-clearance capability means air passengers can also fly into American airports that are not equipped with customs officers, most notably Washington's Reagan National Airport.The expansion comes as Obama's national security adviser, Susan Rice, told CBC News Wednesday that the US is looking for much more information sharing from Canadian officials to better protect our countries against terrorism."From the US point of view, yes. More [information sharing] is better. We have to do it carefully, we have to do it with very clear understandings and protocols. But we're not serving our people on either side of the border well by hiding or protecting stuff to the point that we're leaving each other vulnerable."Rice was also asked about reports that Canada used the US biometrics system to check each of the 25,000 refugees that came to Canada and if that was normal procedure."I don't know if it's normal for countries to utilize our biometrics process, but given that our systems are so linked and we have the ability to share, we think that's mutually beneficial," she said.