The House ethics committee announced Friday it will begin a preliminary investigation into allegations of possible misconduct by House Speaker Jim Wright.

The panel's decision to proceed with an investigation marks the first time this century that a House speaker was the target of an ethics probe.Wright, D-Texas, said the complaints were "politically motivated," and expressed full confidence he will be vindicated by the committee.

Rep. Julian Dixon, D-Calif., chairman of the ethics committee, said the committee's decision was unanimous. He said Wright had been notified and "he has pledged his full cooperation."

Dixon said the committee's probe will focus on six questions involving Wright's activities - his efforts on behalf of Texas savings and loan institutions, his contacts with the Interior Department concerning a Texas oil firm, whether campaign funds were used to pay for the publication of Wright's book, the use of a staff aide to prepare the book for publication, the use of a condominium in Fort Worth, Texas, and Wright's dealings with officials of the Federal Home Loan Bank Board.

The committee met 8 1/2 hours behind closed doors Thursday night before reaching a final agreement to launch the investigation and determine what points would be considered.

Shortly before Dixon's announcement, Wright met with reporters and released a narrative of his activities that have been called into question and declared, "I have absolute confidence . . . the (ethics) committee will discover that no rule of the House was violated."

The 23-page narrative was accompanied by a half-inch-thick pile of supporting materials relating to his finances and unusually high royalties on a book he wrote, one of the items that have been called into question. Wright's lawyer briefed reporters on the documents, and Wright later discussed them in detail with reporters.

Committee members realize, Wright said, that "lots of the charges are politically motivated" but nevertheless will conduct a thorough investigation to prove they are groundless. Wright said he was "absolutely anxious" to lay out his case and said it "must be resolved expeditiously."

The lengthy ethics committee meeting came a week after the panel met for 2 1/2 hours on June 2 to consider whether to begin a probe of possible misconduct by Wright, as urged by House Republicans and the citizens lobby Common Cause.