St Kilda has signed Claremont forward Tom Lee through an AFL pre-draft selection deal with the GWS Giants.

The Saints have agreed to give the Giants pick 12 in the national draft for the 21-year-old, who was a key part the Tigers' 2012 premiership.

St Kilda will also get picks 24 and 43 from GWS.

"This was a breakout year for Tom where he developed into a dominant forward in the WAFL competition. He was also a key contributor in Claremont's premiership side," St Kilda coach Scott Watters said of his fellow West Australian.

Lee was previously drafted by Adelaide as pick 60 in 2008 but returned to WA after a year without featuring in the AFL.

He said he was surprised with how quickly things developed, adding: "For now I want to hopefully put myself in good stead to have a solid pre-season and I just want to play my role and play well for the club."