Cast member Charlize Theron and actor Sean Penn attend the premiere of "A Million Ways to Die in the West" in Los Angeles, California May 15, 2014. The movie opens in the U.S. on May 30. REUTERS/Mario Anzuoni (UNITED STATES - Tags: ENTERTAINMENT)

After a whirlwind, five month romance, Sean Penn and Charlize Theron are reportedly ready to wed.

According to sources close to the couple, quoted in Us Weekly, the Hollywood pair are eager to settle down.

“They absolutely want to get married,” said one insider, while another added: “They want to grow their family”.

The romance between Penn and Theron sparked at the beginning of this year, but the couple have known each other for years.

Theron said as much in the June issue of Vogue, and revealed that their love grew out of friendship.

“Sean and I have known each other for 18 years,” the 38-year-old said.

“We were just really good friends. And it's been slow going because you are aware that you could screw that up and lose it.

“We had to think about it. But at the end of the day, it was somewhat effortless.”

The actress was also keen to express how happy she was with Penn in an interview with Esquire.

“The people who really love me can see the effect it has had on me,” she said. “It was nice to be single and now it's nice to be not single.”

Before they make any firm wedding plans however, there is work to be done.

Penn will direct Theron, alongside Javier Bardem, in the romantic drama The Last Face. – Tonight Reporter and Daily Mail