ET caught up with the actor at the 2019 G'Day USA Los Angeles Gala to Honor Australians, where he briefly spoke about his friend's battle with cancer.
"From what I hear talking to her she's fine," Travolta told ET's Keltie Knight. "I think she even made a public announcement in her own video, [saying] that she was fine."
Earlier this month, Newton-John slammed false reports for exaggerating her illness and alleging she's on the brink of death in a video posted to her Facebook page.
"Happy New Year, everyone! This is Olivia Newton-John, and I just want to say that the rumors of my death have been greatly exaggerated, to quote the famous quote [atributed to Mark Twain]," the 70-year-old actress said at the time. "I'm doing great and I want to wish all of you the happiest, healthiest 2019 that is possible."
"Thank you all for your wonderful love and support, for me and for my Olivia Newton-John Cancer Wellness Center in Melbourne, Australia," she added. "Thank you so much!"
Newton-John revealed back in September during the Australian news program Sunday Night that she's battling cancer for a third time and in recovery again. "I'm one of millions in this fight, in this journey," she said. "A lot of people see it as a fight and wherever you choose to see it, that’s your prerogative. ... I see it as part of my mission, maybe."
"There are other people out there doing much, much worse than me," she continued. "And I'm a very privileged person and I'm very aware of that. I have nothing to really complain about."
Newton-John was first diagnosed with breast cancer in 1992. She beat the disease after months of chemotherapy treatments and a partial mastectomy but revealed in May 2017 that the breast cancer had returned, spreading to her shoulder. Hear more in the video below.