Robin Thicke's girlfriend fuels rumors the couple has wed

Robin Thicke's model girlfriend has fueled rumors the couple has secretly wed by posting a cryptic vacation shot on Instagram.

April Love Geary, 21, posed with her back to the camera, showing off her envious curves and bikini bottoms sporting the initials 'ALT'. Eagle-eyed fans were quick to note the letters could spell out April Love Thicke, and suggested the couple might be husband and wife.

Geary simply captioned the shot, "His", only firing up the speculation.

The latest shot comes two months after the loved-up couple got matching tattoos on their ring fingers of each other's initials, although Geary's spelled out 'ALT' again.

"2 years strong, love you," she wrote.

A source close to Thicke insists the singer and his girl are not married.

The Blurred Lines hitmaker split from ex-wife Paula Patton in 2014 and he and Geary made their debut as an official couple at the Cannes Film Festival in May, 2015.