(CBS News) ISLAMABAD - Senior Pakistani security officials urged intense new security measures for lawmakers after the Taliban threatened to attack members of parliament if they vote to re-open a crucial land supply route for U.S. and other Western forces in Afghanistan.
According to Reuters, the threat was made by Ehsanullah Ehsan, a spokesman for the Tehrik-e-taliban Pakistan (TTP) movement, in which he told the wire service, "If the parliament decides to restore NATO supplies, we will attack parliamentarians and their overlords."
Two Pakistani officials dealing with security who spoke to CBS News confirmed the threat.
A Pakistani intelligence official in the northern city of Peshawar who spoke to CBS News on condition of anonymity called it "a very genuine threat. It is a major cause of concern for us."
Another source - a senior Pakistani police officer who spoke to CBS NEWS in the central city of Lahore - added they have "credible reports" that the Taliban will target members of parliament who support a re-opening of the supply route.
The route was blocked by Pakistan's government last November after 26 of its army soldiers were killed in a NATO helicopter attack which had targeted two of Pakistan's border posts near the country's frontier with Afghanistan.
The threat on Sunday came a day before the parliament's upper and lower houses begin debating a report by the parliament's committee on national security. The committee, after discussing future ties with the U.S. and other countries with troops in Afghanistan, last week presented its findings.
Though the parliament is yet to approve the report, at least three members of parliament have told CBS News that they believe parliament will eventually vote to re-open the supply route.
More crucially, on Tuesday U.S. President Barack Obama and Pakistan's Prime Minister Yusuf Raza Gilani are scheduled to meet in Seoul, South Korea, on the sidelines of a global nuclear security summit.
Pakistani officials have said that the meeting between the two leaders will likely discuss prospects for reopening the supply route, although U.S. officials have been cautious in drawing a conclusion until such time that the parliament comes out publicly with its findings.
But Western diplomats closely tracking U.S.-Pakistan diplomacy concerning the supply route have said that reopening the border is essential for the Obama administration to demonstrate to foreign policy observers in the U.S. that relations with Pakistan - and efforts to stabilize Afghanistan - are beginning to improve.
"A continued deadlock in ties with Pakistan will expose President Obama to criticism from foreign policy watchers in the U.S.," said one senior European diplomat in Islamabad who spoke to CBS News Sunday on condition of anonymity. He added, "The U.S. needs to undo this deadlock [in relations with Pakistan] and move on, especially in an election year when the [Obama] administration needs to demonstrate back home that it has a full control over Afghanistan."