Pope Francis met with the city official who was jailed for refusing to issue same-sex marriage licences during his historic visit to the US and Cuba. Kentucky county clerk Kim Davis said the Argentinian pontiff had words of encouragement for her during a brief exchange in Washington, DC.

"It was really very humbling to even think that he would want to meet me or know me," Davis told broadcaster ABC. "He said 'stay strong.' That was a great encouragement," Davis, an Apostolic Christian, said. "Just knowing that the Pope is on track with what we're doing and agreeing, you know, it kind of validates everything."

Her lawyer, Mat Staver, said that his client and the pope met in private for 15 minutes at the Vatican Embassy in Washington, DC, a circumstance that Vatican spokesman Rev. Federico Lombardi did not deny, saying only he had no comment on the subject.

Francis had already appeared to back Davis's decision to refuse a marriage license to a homosexual couple, as he told reporters, during his flight back to Rome, that conscientious objection was a human right to be defended.

Asked if individuals have a right to refuse to abide by some laws, including the one on issuing marriage licenses to gays, Francis said that conscientious objection has to be present into every judicial structure "because it is a right".

"I can't have in mind all cases that can exist about conscientious objection but, yes, I can say that conscientious objection is a right that is a part of every human right," he said, according to Reuters. "And if someone does not allow others to be a conscientious objector, he denies a right."

The Kim Davis case has surged into national significance in the US after 2016 Republican presidential candidates Mike Huckabee and Ted Cruz attended a rally with her after her release.

The 50-year-old was jailed for five days in September for refusing to comply with the order of US district judge David Bunning to issue licenses to homosexual couples, in the aftermath of a Supreme Court ruling that made gay marriage legal across the nation. The woman justified her decision saying she could not act against her faith.