Robert Pattinson and FKA twigs' wedding is reportedly "off the agenda."

Robert Pattinson and FKA twigs

Robert Pattinson and FKA twigs

The 29-year-old actor and the 'Two Weeks' hitmaker, who got engaged in March after six months of dating, have allegedly "drifted" apart while he is filming 'The Lost City of Z' in Northern Ireland, but are still trying to make their romance work.

A source said: "[Their] wedding is off the agenda, [but] they haven't called off the engagement.

"They've definitely drifted and have barely spoken while he's in Belfast and she's been in the States."

The 27-year-old singer has been staying at the 'Rover' star's home in Los Angeles while he is away, but he isn't comfortable around many of the people on "Team twigs."

The insider told PEOPLE.com: "Rob has never been at ease with twigs' entourage."

The 'Twilight Saga' heartthrob is scheduled to fly to Colombia next month to film scenes in the jungle, and the source predicts it "is bound to create further distance between them."

It was previously reported the couple had pushed back their wedding because they couldn't decide what kind of celebration to have.

A source said last month: "She talks about keeping it real and low-key and then wants an elaborate glamorous Baroque affair. She was even talking at one stage about having a masked ball.

"It will now be bigger but how big, nobody's quite sure at this moment in time. There's no fixed [wedding] date but will probably be late in the year."