HOME ALONE star Macauley Culkin and his longtime girlfriend Mila Kunis are reportedly shopping for an engagement ring after deciding to wed.

The couple, who started dating in 2002, were spotted checking out rings at a number of Beverly Hills jewellers on 4 January (06), according to American publication In Touch, and friends claim they're planning to wed this year.

A source says, "Mila's looking for a ring that's unique and may even opt for a ruby instead of a diamond."

Culkin, 25, was previously married to actress Rachel Miner, but the union lasted just two years. They divorced in 2000.