LONDON (AP) _ IOC president Juan Antonio Samaranch has taken a dramatic step to combat the worst ethics scandal in IOC history, banning committee members from visiting cities bidding to be Olympic hosts.

Samaranch also called Monday for a special executive board meeting for next month to act on the Salt Lake City bribery scandal and consider changes in the system for selecting Olympic cities.

``The trips of IOC members to candidate cities, these are terminated,'' Samaranch told the Swiss newspaper Le Matin.

The visits by International Olympic Committee members to bidding cities have long been considered fraught with the dangers of corruption. The members fly first-class, stay in the best hotels and are wined and dined _ all in an attempt to win their vote.

In recent years, the IOC has attempted to tighten the rules by restricting the visits to three days and putting a $150 limit on the value of gifts offered to members.

A ban on trips presumably would take effect immediately, meaning IOC members won't be able to visit the cities bidding for the 2006 Winter Olympics _ Sion, Switzerland; Turin, Italy; Zakopane, Poland; Klagenfurt, Austria; and Helsinki, Finland.

The only IOC member ever to quit in an ethics scandal, Robert Helmick, said first-class airfare for each member and spouse, worth about $5,000-$10,000, was ``the minimum that's expected (from a bid city) before they get to the gifts. That's tit for tat.''

Helmick, who resigned as an IOC member and U.S. Olympic Committee president in a conflict-of-interest case in 1991, said a small group of IOC members are willing to turn over blocks of votes in return for ``extravagant gifts and favors'' from cities seeking to stage the Olympics. He said the gifts could range from fur coats to shopping sprees for thousands of dollars in clothes.

He also said Samaranch failed to pay enough attention when allegations of corruption first surfaced 10 years ago.

``He has done a lot of great things for the Olympic movement,'' Helmick said. ``But he did not take this seriously or act promptly, for whatever reason.''

The IOC visits have come under scrutiny following accusations of misconduct surrounding Salt Lake City's successful bid for the 2002 Winter Olympics.

Salt Lake officials have admitted that six relatives of IOC members were among those who benefited from nearly $400,000 in scholarship aid from the bid committee.

There is growing evidence of other favors for IOC members, including free medical care and gifts in excess of the $150 limit.

In addition, the son of David Sikhulumi Sibandze, an IOC member from Swaziland, worked as a paid intern with the Salt Lake City government.

Sibandze told The Associated Press his son, Sibo, got the job with the city on his own after receiving a masters degree from the University of Utah.

``It was my son's own initiative to apply to the city. I remember he phoned me to say he was now working for the city council,'' Sibandze said. ``He phoned me to say, `Oh, Dad, I got a job.' ''

USA Today, citing former Swedish Olympic official Wolf Lyberg, reported today that Sibo Sibandze received a scholarship 12 years ago when Falun, Sweden, was bidding for the 1992 Winter Olympics. However, Sibo Sibandze chose not to attend the Swedish university.

IOC vice president Dick Pound, leading an investigation into the Salt Lake case, gave a guarded welcome to Samaranch's ban.

``As a response to the present crisis, it's probably a good thing to do,'' he said from Montreal. ``Whether it should be taken as the definitive, long-term response or not, it's too early to say.''

The USOC also will investigate, with former Senate majority leader George Mitchell heading a five-member panel that will begin work early next month. Other members of the panel include Kenneth Duberstein, a White House chief of staff under President Reagan; Donald Fehr, executive director of the baseball players union; Roberta Cooper Ramo, a New Mexico attorney who was the first female president of the American Bar Association; and Jeff Benz, a member of the USOC's athletes advisory council.

In addition to the Salt Lake City allegations, the commission will examine ethics rules governing future bids by U.S. cities, starting with the selection of a candidate for the 2012 Summer Games, which is in progress.

In a sign that Samaranch wants the Salt Lake matter dealt with quickly, he called a special meeting of his executive board for Jan. 23-24.

A board member, speaking on condition of anonymity, said the panel was prepared to take immediate ``necessary measures'' on the recommendations of Pound's inquiry.

Samaranch has said any IOC members found guilty of corruption will be expelled or asked to resign.

The executive board also will use the meeting to consider ways of reforming the procedure for selecting host cities.

``Definitely in the executive board, there is a feel for a need for change,'' the board member said.

Proposals include the establishment of a small ``electoral college'' of executive board members and representatives of national Olympic committees, international federations and athletes.

The group could either select the winner, or choose two finalist cities and then let the entire membership vote.

Changing the procedure would require a two-thirds majority of the 115-member IOC assembly.

Samaranch said taking the vote away from the rank and file is like asking members ``to cut off their heads.'' But he said under ``special circumstances'' the members should agree to changes.

The reforms could be adopted in time for the vote in June on the 2006 Winter Games.

Pound urged caution before overhauling the procedure. He said the status quo offers a ``more statistically reliable'' system for choosing the right city.

``If you narrow it down to an electoral college or the executive board, you may not cover all the global factors,'' he said. ``The real question is not the peccadilloes of a few minority of IOC members. It's whether you get the overall picture of the Olympic Games.

``The standard of conduct is extremely serious, but has to be put in perspective.''