Jennifer Aniston and John Mayer are planning a "trial marriage".

The couple — who have been dating for three months — are said to be keen to test the strength of their relationship, and think Mayer moving into Aniston's house is the perfect first step.

A source said: "John wants to settle down as much as Jennifer does.

"What's more, he’s been telling her that he thinks she is the one and she believes him."

Mayer's move into Aniston's Beverly Hills mansion is set to happen after his tour ends in September.

The couple are also reportedly planning a family.

The source added to Grazia magazine: "John is the first guy since Brad who has talked seriously about having children and Jennifer is very excited about it."

Aniston was previously married to Brad Pitt for five years. They separated in 2005 amid allegations he was cheating on her with actress Angelina Jolie, with whom he now has six children.