Could Matthew McConaughey and Woody Harrelson be brothers?

Matthew McConaughey stated the pair had found out that his mother knew Harrelson's father as ITV News' Warren Nettleford reports.

Matthew McConaughey says he believes his True Detective co-star and close friend Woody Harrelson could be his half-brother.

Speaking on Kelly Ripa's Let's Talk Off Camera podcast, the actor stated the pair had found out that McConaughey's mother knew Harrelson's father, possibly 'intimately'.

“You know, where I start and where he ends, and where he starts and I end, has always been like a murky line,” McConaughey said.

“And that’s part of our bromance, right? My kids call him Uncle Woody. His kids call me Uncle Matthew etc, etc. And you see pictures of us and my family thinks a lot of pictures of him are me. His family thinks a lot of pictures of me are him.”

“In Greece a few years ago, we’re sitting around talking about how close we are and our families,” McConaughey said.

“And my mom is there, and she says, ‘Woody, I knew your dad’… Everyone was aware of the ellipses that my mom left after ‘knew.’ It was a loaded K-N-E-W.”

“We went on to unpack what this ‘knew’ meant and did some math and found out that (Harrelson’s) dad was on furlough at the same time that my mom and dad were in their second divorce. Then there’s possible receipts and places out in West Texas where there might have been a gathering, or a meeting, or a ‘knew’ moment.”

Harrelson's father, Charles, was a convicted contract killer who was first convicted for armed robbery in 1960.

He jailed for murder and released on good behaviour five years later, and would go onto assassinate a federal judge.

He also claimed to have taken part in the murder of President John F. Kennedy. His claims were later rubbished by the FBI.

Harrelson's father also admitted that he had been involved in dozens of murders beginning in the early 1960's.

Harrelson has spoken in the past of growing up with his father largely absent from his life with his mother and siblings. The actor said he used to visit his dad in prison, and described him as more of a 'friend' than father figure.

Charles Harrelson died in jail in 2007.

Both Harrelson and McConaughey have two brothers each.

The pair have appeared onscreen together in True Detective and the film EDtv, and are poised to reunite in an Apple TV+ show called Brother from Another Mother, where they play fictionalised versions of themselves.

McConaughey added that the pair are on the cusp of doing a DNA test to verify their suspicions.

However, McConaughey stated he is more reluctant than Harrelson to partake in the test in case it turns out his father may not be his biological parent "after 53 years of believing that."

The two actors first met in 1997 while working on Ron Howard’s “EDtv,” although they disagree about the precise moment.

“There was tequila involved,” McConaughey quipped in a video on his verified YouTube channel.

He first remembers meeting Harrelson at a costume fitting in San Francisco for “EDtv,” when Harrelson walked in wearing “bike shorts, professional bike top and he’s still got his professional bike riding shoes on that he’s walking the streets of San Francisco in.”

Since then, McConaughey and Harrelson have starred in the movie “Surfer, Dude,” and in the widely acclaimed police thriller “True Detective” series together.

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