NATO and Russian sources said recent attacks along the international military organization's supply route through Pakistan have prompted NATO to speed up creation of a safer railway route, The Times of London reported Saturday.

"It'll be weeks rather than months," an unidentified NATO official said of the route's construction. "Two months max."

The sources said the former Soviet central Asian states of Kazakhstan and Uzbekistan are in final negotiations with NATO officials regarding the new route.

News of the proposed NATO route to Afghanistan follows growing concern among NATO and U.S. officials regarding this year's Pakistan attacks.

"We're all increasingly concerned," Adm. Mike Mullen, chairman of the U.S. Joint Chief of Staff, said Wednesday. "But in that concern, we've worked pretty hard to develop options."

The Times said, according to its sources, while NATO is eyeing a northern corridor route through Russian negotiations, the organization is also examining a supply route through the central Asian state of Turkmenistan.