[JURIST] The US Senate Wednesday approved key amendments to an immigration reform bill that would create an additional 370 miles of fencing along the US-Mexico border and would deny the possibility of acquiring citizenship to illegal immigrants convicted of certain criminal offences. The border fencing amendment introduced by Senator Jeff Sessions (R-AL) [official website] that passed 83-16 [roll call] would authorize triple-layer fencing along an unspecified route and the creation of an additional 500 miles of vehicle barriers to hinder unauthorized crossings. Referring to his proposal in light of the President's announcement of additional measures [JURIST report] Monday night, Sessions said:

A border fence, combined with National Guard forces, increased border patrol agents and more bed space for arrested illegal aliens, will help us reach a tipping point where the scales tip from illegality to legality. If we continue to send signals like this, that the open border days are over, people will know that it makes more sense to apply and come into our country legally, according to our laws, rather than trying to come in illegally.

Read his full statement on the passage of the amendment [text]. Some border barricades already exist, most notably a 14-mile stretch south of San Diego [NPR backgrounder]. Late last year the US House narrowly approved a border security and immigration bill that included plans to build a security fence across 621 miles of the Mexican border [JURIST report] and authorized the US Department of Homeland Security to study the possibility of placing barriers across the famously "undefended" US border with Canada, the longest undefended border line in the world. CBS News has more.

Earlier Wednesday the Senate approved [Kyl press release] by 99-0 another amendment [PDF Congressional Record text] sponsored by Senators Jon Kyl (R-AZ) and John Cornyn (R-TX) [official websites] that will prevent any illegal immigrant who has been convicted of a felony or three misdemeanors from "participating in a program that places them on a pathway to citizenship." The current version of the Comprehensive Immigration Reform Act of 2006 [text] includes what critics call an "amnesty" program, a compromise solution [JURIST report] that provides a pathway to citizenship for illegal immigrants who have worked in the country for three to five years and have met eight criteria, including filing up-to-date state and federal tax returns and proficiency in English. On Monday, the Senate rejected [JURIST report] a conservative amendment requiring that border security measures be finished and operational before any such "amnesty" plan is implemented. House Republicans have repeatedly expressed their distaste for any program allowing illegal immigrants to eventually apply for citizenship. AP has more.