A host of senior Clinton administration officials yesterday offered upbeat predictions for next week's gathering of the World Trade Organization in Seattle, despite indications that the session may be marred by vigorous domestic protests and by irreconcilable disagreements by the 135 nations in attendance.

A White House effort to elevate the international profile of the summit--and to give a boost to the negotiations--by inviting several world leaders to attend fell apart when other governments made clear they were not interested or not able to make a last-minute trip to the United States.

President Clinton, in a brief appearance yesterday, portrayed the invitations as an almost whimsical effort on his part. "Just almost at the last minute, I thought, well, since I'm going to be out there a day and a half or a day, that if anybody wants to come, other people who are interested in this, I ought to give them a chance to come," he said. "But I think we decided to do it so late, it was just more of a logistical problem than anything else."

The Seattle summit, which Clinton will attend as leader of the host nation, is to arrive at an agenda for the next round of WTO negotiations. Expectations overseas and among some business groups here for the summit have become clouded by the failure of trade envoys meeting earlier this week in Geneva to come to agreement on the agenda.

Among the contentious issues for the next round of trade talks is lowering barriers to agricultural trade--farmers in Europe in particular enjoy large subsidies--and deciding whether the WTO should adapt minimum labor standards for its member nations, as the United States advocates in the face of opposition from developing nations.

U.S. Trade Representative Charlene Barshefsky, at a White House briefing yesterday, cautioned against reading too much into the impasse in Geneva. She said the openings of earlier trade rounds have followed "exactly the same pattern--dire warnings, grave concern--and everything at the end comes out just fine."

"You see, at the end, everyone knows that failure is not an option, so it will come together," she said. "I have a very high degree of confidence in that."

A senior White House official involved in WTO planning was even blunter. While lower-level trade envoys were negotiating in Europe, only the trade ministers gathering in Seattle have the authority to reach an accord, the official said. "Everybody is sounding pessimistic for public consumption," the official said, while the reality is that nations are "holding their cards [to negotiate] the last bit."

While Clinton's hopes for a constellation of foreign leaders trumpeting a free trade message are not coming to pass, speculation continues to circulate that one leader Clinton is not eager to see will attend: Cuban dictator Fidel Castro.

Some business lobbyists said they believe it is likely Castro will make a last-minute bid to attend. State Department and White House officials said more than 30 representatives from Cuba--a WTO founding member--have requested and received visas, but they have not received a request from Castro.

"We don't really know whether he intends to come," said an administration official. "Many in the Seattle community are encouraging him to come. . . . At the end of the day it's hard to imagine us denying him a visa, but so far he hasn't asked."

There will be other sources of controversy: labor and environmental groups are planning demonstrations and protests at Seattle.