Louis Tomlinson's estranged father has reportedly threatened to drop a "bombshell" unless the One Direction member reconciles with him. 

Troy Austin, 46, was hoping that his son's yet-unborn baby would bring them closer together and heal their relationship. Tomlinson is expecting a child with his friend Briana Jungwirth. 

But Austin, who hasn't spoken to the 23-year-old boy band member since they argued during a telephone call three years ago, is allegedly now threatening to shake up Tomlinson's life if he continues to ignore him.  

A source told the Sunday People that Austin has always wanted to repair their relationship "but if Louis isn't prepared to do so, he's told a few friends he has something which would really throw a grenade in things." 

The source added that Austin sees it as his last chance to get his son's attention and he has said that "he will drop the bombshell if he feels it's the only option he's got left." The insider added that Austin knows that it would cause another big rift in the family, but he is reportedly starting to feel like he has nothing left to lose. 

Austin and Tomlinson's mother Johannah split up when the boy band member was only five years old. The singer took the name of his stepfather, Mark Tomlinson. 

The 46-year old previously revealed that he would like to be involved in his grandchild's life, explaining that he missed out on his son's life and he would like to make up for that. 

Of his son, Austin said, "I'm sure he will be a great dad if he commits to it fully. I'd hate to think of him having the sort of relationship with his child that we had." 

Back in March 2013, Tomlinson took to Twitter to lash out at the Sunday Mirror after the newspaper published an interview with his father. In the interview, Austin said that he had taken the 1D member's half-sister, Georgia, to the Nottingham leg of the band's tour to see her brother perform and revealed that he attempted to go backstage to speak to his son after the show, but was told that it wouldn't be possible. 

Tomlinson has yet to comment on the report.