ST. LOUIS (AP) _ St. Louis Blues forward Jorgen Pettersson will be sent to the Hartford Whalers to complete a February trade between the National Hockey League clubs, a St. Louis radio station reported today.

Dan Kelly, the Blues' announcer, reported on radio station KMOX that Pettersson, 28, will join goalie Mike Liut in the deal that brought goalie Greg Millen and forward Mark Johnson to St. Louis.

A Blues' public relations official said he knew nothing about the report. Ron Caron, vice president and director of hockey operations, was unavailable for comment.

St. Louis traded Liut to Hartford on Feb. 22 in exchange for Millen and Johnson. At the time, the Blues said they would also give Hartford ''future considerations'' at the end of the season to complete the deal.

The Blues were eliminated from the Stanley Cup playoffs on Saturday, while Hartford did not qualify for postseason play.

Pettersson, a native of Sweden, has played five seasons for St. Louis and scored at least 20 goals in each one. His highest total was 38 in 1981-82. He dropped off this year with a total of 23 goals.