It read: "The only lie I ever told you is that I liked you when I already knew I loved you."
SO sweet, right?
Liam then added a slew of emojis alongside his post that were tell tale signs he was talking about former X Factor judge Cheryl. One was of a girl wearing a crown and another of a rose - y'know because Cheryl just happens to have a huge rose tattoo across her back and bum...
Fans were quick to link Liam's post to Cheryl, with one user commenting: "Lucky Cheryl." Another said: "Wish you both the best."
Others, meanwhile, took it to be about them. One fan replied to Liam: "You know [I] love you too."
Liam's Instagram post comes after Cheryl recently finalised her divorce with ex-husband Jean-Bernard Fernandez Versini. They were granted a decree nisi on 20 October, with Cheryl's rep confirming: "Cheryl Fernandez-Versini and Jean-Bernard Fernandez-Versini have today obtained Decree Nisi in their divorce proceedings. No further comment will be made and they ask for their privacy to be respected."
Cheryl and Jean-Bernard had married in a secret ceremony in July 2014, and reports claiming they were set to divorce surfaced at the beginning of this year.
Cheryl is now dating Liam and they first went public with their romance, after much speculation and teasing social media posts, in March, before making their red carpet debut as a couple at the Global Gift Gala in Paris back in May.
Since then, it has been widely speculated that Cheryl is now pregnant with Liam's baby, but again, she has not addressed the rumours and is instead keeping us all guessing.
Liam, meanwhile, has been working on music over in LA and has teased that he will be embarking on a solo career. He isn't the first One Direction star to go solo, as Zayn Malik kicked off his solo career shortly after leaving the band in March 2015, while Niall Horan has recently released his very first solo track, 'This Town'.
That doesn't mean that he, Liam and the remaining boys Harry Styles and Louis Tomlinson won't be getting back together, though. Niall confirmed that One Direction's hiatus will come to an end in the "foreseeable future" during an appearance on The Graham Norton Show.
He said: "For now we are doing our own thing. We can't put a date on it but it won't be in 50 years. It's in the foreseeable future. We've talked about it, but for now we'll just play it by ear and see what happens."
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