Speaking to CNN's Jake Tapper, Fallin, the co-chair of the party's platform committee, would only say that the party will "remain pro-life."
"I know that Donald Trump has said as a candidate that he believes in life, and I think the majority of the Republican Party does believe in life -- that has been an important part and plank of our platform as a political party," Fallin said.
The Oklahoma governor -- and potential Trump running mate -- said the platform's decisions will be up to the party even though Trump is now the Republican standard-bearer.
"He will have representation -- he's going to be the presumptive Republican nominee -- and certainly he will have a voice with his people, who will make recommendations, too," Fallin said. "But in the end, this platform is driven by grassroots Republican people throughout the nation who will represent the very values and principles of the Republican Party."
"Just to be clear, you can't guarantee that the platform will make good on Donald Trump's promise? It will be up to the people that make the decision, the 100 or so delegates?" Tapper asked Fallin.
"That's right," she responded.
In April, Trump was asked about the GOP platform on abortion in an interview with NBC's Savannah Guthrie
"The Republican platform every four years has a provision that states that the right of the unborn child should not be infringed," Guthrie said. "And it makes no exceptions for rape, for incest, for the life of the mother. Would you want to change the Republican platform to include the (abortion) exceptions that you have?"
"Yes, I would. Yes, I would. Absolutely," Trump said. "For the three exceptions, I would."
The position puts Trump at odds with many conservatives already suspicious of Trump's ideology and loyalty to Republican values, and the billionaire has offered various opinions on abortion.
In March, he made headlines when he said women who undergo the procedure should face "some form of punishment"
should the practice be outlawed. He quickly backed away from the remarks, releasing a statement in which he said that women who obtain abortions are victims and that doctors who perform the service are the ones who should be punished.
And in late June, an attendee at a Trump campaign event
said he was "opposed to the murder of unborn babies being legal," to which Trump replied, "We are with you." Campaign aides didn't respond to a request for further details as to whether Trump meant he opposed abortion rights in all circumstances.
While the official party platform doesn't explicitly outline or endorse any abortion exceptions, GOP presidential candidates in the past have supported them, including Mitt Romney, John McCain and both Bush presidents.
Early in the 2008 primary process, McCain voiced a desire
to change the party's platform on abortion to accommodate for the same three exceptions Trump mentioned in April. He later dropped his call to update the platform after he secured the Republican nomination.
The platform process, which will begin on Monday, involves specific committees made up of the elected delegates from different states who debate and vote on various issues that will form official GOP policies. Candidates, however, are not legally bound to adhere to them.