Senate banking committee members have elicited more information about the Obama Administration’s sketchy Sept. 6 proposal for a new federal infrastructure bank.

Testifying at a Sept. 21 committee hearing, Roy Kienitz, under secretary of transportation for policy, conceded the bank proposal was “vague, and deliberately so.” He told reporters that officials hope to release details early in 2011, with the next budget proposal, but added, “Plans could change.” He testified that, although the bank initially would focus on transportation, “It certainly could go more broadly than that.”

Sen. Richard Shelby (R-Ala.) said he feared the bank would be another Fannie Mae or Freddie Mac, government-backed entities whose financial straits led to large federal-aid infusions.

But Alan B. Krueger, an assistant Treasury secretary, said the bank would be structured differently. No action on the bank plan is expected this year, but it’s likely to be part of the debate on a new multiyear transportation bill next session.