Rhys Ifans' parents are thrilled he is marrying Sienna Miller and can't wait to become grandparents.

Sienna, who accepted Rhys' marriage proposal earlier this month, has been given the seal of approval by her future in-laws Beti and Eirwyn Evans who have urged her to start a family soon.

Rhys' mother Beti said: "Rhys is nearly 40 so we would be delighted if Sienna gave us a grandchild. She would make a great mother. She is lovely."

Rhys changed his surname from Evans to Ifans after deciding to adopt the Welsh spelling of his surname.

The couple, who are planning to move to Rhys' native Wales, are set to marry on a private Mexican island later this year.

The 26-year-old actress - who started dating the 'Notting Hill' star last August - is said to have chosen the idyllic island of Isla Mujeres, located eight miles off the coast of Mexico's Cancun.

A source said: "This is the perfect location for Sienna's wedding. It's in the middle of nowhere, so it's perfect for a private ceremony."

Sienna is said to be keen to tie the knot before Rhys launches his music career with his new band The Peth.