(ed. note: This post has been updated to reflect late-breaking news as of Wednesday afternoon.)

House transportation committee chairman Jim Oberstar’s (D-MN) plan for a three-month extension of the 2005 federal infrastructure law, appears on track for a vote this afternoon, despite reports that GOP opposition unexpectedly derailed consideration of the bill.

House transport committee chairman Jim Oberstar (D-MN) (Photo: Capitol Chatter)

A full copy of the bill is available here. But the bigger question of what happens next, with just three legislative days left until the nation’s transportation law expires, remains unanswered.

Reports emerged this afternoon to suggest that the three-month extension had been pulled from from the House’s "suspensions calendar," used to pass non-controversial
bills that can obtain a two-thirds majority of the chamber.

"The Republican leadership is, for whatever reason, opposing our bill," Oberstar spokesman Jim Berard said in an interview. "I don’t understand why — it’s a clean extension, no diff from the 12 extensions we did when we were working on SAFETEA-LU [the existing federal transportation bill] five years ago when Republicans were in charge."

But a GOP source told Streetsblog Capitol Hill that the three-month extension would be taken up on the suspensions calendar later today, generating even more uncertainty over the bill’s ultimate fate. Meanwhile, two new wrinkles in the story are emerging this morning.

First, the subscription-only BNA newsletter reports that Oberstar’s three-month proposal does not include language preventing the cancellation of $8.7 billion in highway contract authority, which is set to take effect next week unless Congress acts. The road lobby is growing increasingly concerned that it could lose out on the money, which Senate environment committee chairman Barbara Boxer (D-CA) promised to restore during floor debate over her proposed 18-month extension of transportation law.

Second, some doubt is beginning to emerge over whether Boxer’s 18-month plan will pass this month. The Senate’s No. 2 Democrat, Dick Durbin (D-IL), said yesterday that his colleagues are mulling over whether to pass a short-term or long-term extension of the 2005 transport law.

Sen. Mark Warner (D-VA) also told Streetsblog Capitol Hill today that he has "been hearing that there may be just a three-month bill" agreed upon by both chambers of Congress.

With the House also sending the Senate a three-month extension of the law governing federal aviation programs, the upper chamber could decide to bundle the transportation and aviation measures together. Still, a short-term extension is unlikely to sit well with the Obama administration, which continues to seek an 18-month delay.

Streetsblog Capitol Hill has requested comment from Boxer’s office on how she plans to proceed following the House’s vote today. We’ll update you as more becomes available.