WASHINGTON — As the countdown clock toward a deal to avert a federal shutdown neared zero, and for all the talk of reducing the size of government and scaling back federal spending, Democrats complained today that House Republicans were again fixated an age-old sticking point: abortion.

“Republicans want to shut down the government because they want to make it harder for women to obtain the health services they need,” Sen. Harry Reid of Nevada, the majority leader, said today on the Senate floor.

At issue is a provision, known as Title X, that sends federal dollars to Planned Parenthood for family planning and health services such as cancer screenings. Republicans want to allow states to redirect that money away from abortion providers. They also want to eliminate $317 million from the program for the 2011 fiscal year.

“The truth is that the rider regarding Planned Parenthood would bar Planned Parenthood from being paid by Medicaid and other federal programs for providing women with birth control, cancer screenings, HIV testing, and testing and treatment for other” sexually transmitted diseases, Planned Parenthood President Cecile Richards said in a statement. “More than 90 percent of the health care Planned Parenthood provides is preventive.”

Federal law already prevents tax dollars from being used for abortion, except in rare cases. But while Democrats insist the fight is about denying women health care services, two other proposals pushed by the GOP more directly affect abortion rights.

One would halt foreign aid funding to health organizations that promote or provide abortion services, a measure known as the Mexico City rule, as well as to the U.N. Population Fund, which provides reproductive, AIDS prevention and women’s health services.

Another provision would ban the District of Columbia from sending local tax revenue to groups that provide access to abortions.

House Speaker John Boehner, R-Ohio, this morning insisted that spending levels are holding up a potential compromise, not policy issues.

“There’s only one reason that we do not have an agreement as yet, and that issue is spending,” Boehner said. “We are close to a resolution on the policy issues. But I think the American people deserve to know: When will the White House and when will Senate Democrats get serious about cutting spending?”

But Reid dismissed that, saying $38 billion in cuts from current spending levels had been agreed to.

Senate Democrats went full tilt into blaming a power struggle between Boehner and the conservative rank-and-file in the House for the holdup.

“This issue has been brought in by House Republicans at the last moment,” Sen. Dick Durbin of Illinois, the assistant majority leader, said on the floor. “It virtually has no impact on government spending.”

While some reports have had the House negotiations driven by its “tea party” freshman class, the last-minute outcry over abortion shows that social conservatives still have some teeth in the chamber.

Last year, a sustained conflict over abortion services almost derailed the Democratic health care overhaul, with anti-abortion protesters and women’s rights groups descending on the Capitol.

A compromise was ultimately reached and President Barack Obama signed an executive order reaffirming that no funds from the health care bill’s subsidy provisions could be used for abortion.

If no deal on a new budget for the 2011 fiscal year is reached by midnight EDT Friday, most government services will cease and 800,000 workers would be furloughed.