Molly Riley, Associated Press
Senate Minority Leader Sen. Harry Reid of Nev., along with Sen. Charles Schumer, D-N.Y., speaks to media after a policy luncheon on Capitol Hill in Washington, Tuesday, July 21, 2015. Republican and Democratic negotiators in the Senate announced an agreement Tuesday on a six-year highway and transit bill, subject to approval by rank-and-file lawmakers.

WASHINGTON — Republican and Democratic negotiators in the Senate announced an agreement Tuesday on a six-year highway and transit bill, subject to approval by rank-and-file lawmakers.

However, Senate Majority Leader Mitch McConnell, R-Ky., said he and Sen. Barbara Boxer of California, who led the Democratic negotiations, were able to agree only on enough funds to pay for transportation programs for the first 3 years of the bill, leaving open how the later three years will be financed.

"This is a six-year highway authorization that will allow planning for important long-term projects around the country, and the bill provides three years of guaranteed funding for the Highway Trust Fund," McConnell said. "Senators from both parties know that a long-term highway bill is in the best interest of our country."

Senate Minority Leader Harry Reid, D-Nev., said Democratic leaders must first see a copy of the legislation and discuss it with their members.

Both parties were scheduled to discuss the bill at separate luncheons. McConnell moved back the timing of a vote on proceeding to the bill until later in the day.

Sen. Jim Inhofe, R-Okla., said he expected Senate debate on the bill to take about two weeks. Beside the funding issue, lawmakers have also been negotiating changes to a series of safety provisions favorable to the auto, trucking and railroad industries that were approved on a party-line vote by a Senate commerce panel last week. That legislation will be wrapped into the overall bill.

There are likely to be other controversies as well. Some GOP senators have also indicated they will try to add language regarding Planned Parenthood to the bill.And there is expected to be an attempt to reauthorize the Export-Import Bank. Aircraft maker Boeing and the aerospace industry are seeking renewal of the bank, which supports American companies trying to sell products overseas. Conservatives say the bank is corporate welfare.

Congress is facing a July 31 deadline to act. That's when authority for transportation programs expires, eliminating the Transportation Department's ability to process promised highway and transit aid payments to states.

But simply renewing the department's authorization isn't enough. Without an infusion of cash, the balance in the federal Highway Trust Fund is forecast to drop below $4 billion — the minimum cushion needed to keep money flowing to states without interruption — by the end of the month.

The House passed an $8 billion bill last week to keep transportation programs going until Dec. 18 while lawmakers try to work out a longer-term funding plan. But McConnell has said that he wants to pass a bill that keeps programs going at least through next year's presidential election, if not longer.

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