In recent weeks, House and Senate negotiators have failed to close differences over a two-year transportation bill passed by the Senate. It is now up to Congress' top Republican and Democrat to reach a deal on a longer-term bill or a short-term extension of current funding.
The House failed to pass its own, more ambitious highway bill, which sought $260 billion over five years and sought to fast-track TransCanada Corp's controversial Keystone XL oil pipeline project - a provision opposed by President Barack Obama and most Dem ocrats.
In negotiations with the Senate on core transportation provisions, House Republicans have insisted on streamlining environmental reviews of road projects in order to speed up their construction.