Portmeirion produced the Millennium Collection in 1999 and 2000. Most items featured the new Portmeirion Rose, such as the dinner plate:

 

and a range of smaller plates, bowls and dishes:

Here is a 9 inch plate:

One Millennium plate comes from the Botanic Garden range and has the Garden Lilac:

There was a 13 inch platter, made exclusively for Debenhams, featuring the Lily Flowered Azalea, with the green Botanic Garden border. Mine is a trial, with a gold border:

 

Here is the backstamp: