Washington, Jan 6 (IANS): A push by Republican congressional leaders to defund Planned Parenthood could threaten Obamacare repeal because of opposition to the anti-abortion provision by two key GOP senators.

House Speaker Paul Ryan on Thursday said Republicans will move to strip all federal funding for Planned Parenthood as part of the process to dismantle Obamacare, CNN reported.

Republicans have tried for years to zero out all federal funding for Planned Parenthood because the group provides abortion services.

The fight over Obamacare helped trigger a 16-day government shutdown in 2013, and Democrats and President Barack Obama insisted any Planned Parenthood provision targeting the group be removed from a bill to fund federal agencies.

The decision to add the controversial Planned Parenthood language, which is opposed by most Democrats, could have a major impact on getting the Affordable Care Act repeal legislation through the Senate because supporters need the backing of at least 50 of their 52 members and two pro-choice senators, Susan Collins of Maine and Lisa Murkowski of Alaska, would not commit to approving the bill with the Planned Parenthood provision in it.

Senator Rand Paul announced this week to vote against Obamacare repeal because the underlying budget measure it is attached to does not balance and adds to the deficit.

If Murkowski, Collins and Paul voted against the budget bill, it would be enough to torpedo the Obamacare repeal legislation.

"I'm going to wait and see what happens," Collins told the media, indicating she thinks it is too early to decide how she will vote on the bill.

"Obviously, I'm not happy to hear the Speaker wants to include defunding of Planned Parenthood, an extremely controversial issue in the package."

Murkowski on Tuesday said she was still weighing the issue. In 2015, she joined Collins in voting for an amendment to strip Planned Parenthood funding out of a budget bill that would have also repealed much of Obamacare.

But Murkowski ultimately backed the repeal measure even though it had the anti-Planned Parenthood provision, which Obama ultimately vetoed.

When asked her position on Thursday, Murkowski's spokeswoman Karina Petersen said the senator "is concerned about defunding Planned Parenthood as she is a longtime support of it and has opposed broadly defunding the organisation".

Republicans could drop the Planned Parenthood measure, but doing so could spark anger from the right-flank of their party and potentially make it harder to defund the organisation at a later date.

The vast majority of federal money that Planned Parenthood does receive funds preventive health care, birth control, pregnancy tests and other women's health care services.

Democrats also point out that much of the money the group received is through the Medicaid programme, which reimburses health care clinics that provide care to those covered by the federal programme.

Under the long-standing "Hyde amendment" that is attached to annual funding bills, no federal money is allowed to go to programmes that include abortion services, unless they are needed to preserve the life of the mother or are caused by rape.

Democrats immediately denounced the news that Republicans again were working to bar future federal funds for Planned Parenthood.

"This is a priority for the Republicans," said House Minority Leader Nancy Pelosi.

"So I just would like to speak individually to women across America: this is about respect for you, for your judgment about your personal decisions in terms of your reproductive needs, the size and timing of your family or the rest, not to be determined by the insurance company or by the Republican ideological right-wing caucus in the House of Representatives.

"So this is a very important occasion where we're pointing out very specifically what repeal of the (Affordable Care Act) will mean to woman."

Cecile Richards, president of Planned Parenthood Action Fund, told CNN on Thursday that "concerned" women have lobbied against the move throughout the day.

Anti-abortion rights groups point to a letter that the Trump campaign signed in September pledging support for "defunding Planned Parenthood as long as they continue to perform abortions, and re-allocating their funding to community health centres that provide comprehensive health care for women".