BY ANDRES VIGLUCCI, SANDRA MARQUEZ GARCIA AND ANA ACLE

 The U.S. government's handpicked team of mental-health experts failed Monday to win agreement from Elian Gonzalez's great-uncle on a willing hand-over of the boy to his waiting father, virtually ensuring that immigration authorities will formally order him -- as soon as today -- to surrender the 6-year-old.

 Lazaro Gonzalez's reluctance to cooperate with the government's plan for a transfer of custody at a neutral site sets the stage for a flurry of desperate legal moves by his attorneys to block Elian's return to Cuba as federal officials try to bring down the curtain on the drawn-out custody drama.

 In short order, government officials say, they will issue a demand letter to Gonzalez with specific instructions on when and where to turn over the child. The government hopes the transfer will occur before the end of the week.

 The great-uncle's attorneys say they will respond by seeking an emergency order from a federal judge to bar the government from letting the father leave the United States with Elian until a court appeal is concluded. They will also attempt today to revive Gonzalez's custody petition in Miami-Dade family court, asking a judge to conduct a full hearing on the fitness of Elian's father, Juan Miguel Gonzalez.

 Complicating matters were unconfirmed news reports out of Cuba on Monday night indicating that Elian's father was prepared to fly to Miami to pick up his son, but only at a secure location such as Homestead Air Reserve Base. But a spokesman at the Cuban diplomatic mission in Washington suggested there was no such plan, saying ''conditions are not right'' for a turnover in Miami. U.S. officials said they thought a trip to Miami now was unlikely.

 The Miami relatives continued to insist Monday that any transfer take place at their Little Havana home, which is surrounded by protesters.

 That insistence killed any chance of an agreement during Monday evening's meeting between Lazaro Gonzalez and three mental-health experts appointed by the government to recommend a plan for a transfer that would cause as little trauma to Elian as possible.

 LOCATION CHANGE

 The meeting took place hours late after a last-minute change of location forced by Lazaro Gonzalez's refusal to leave the hospital where his daughter is being treated for stress and exhaustion. First scheduled for 1:30 p.m. at Jackson Memorial Hospital, it finally took place at Mercy Hospital at about 5 p.m. after the government refused to postpone it.

 Lazaro Gonzalez was interviewed for about an hour by the three doctors, less than the three hours set aside for the meeting.

 Family spokesman Armando Gutierrez said Gonzalez's 21-year-old daughter, Marisleysis, who regards herself as Elian's surrogate mother, did not participate. Elian was in the hospital visiting Marisleysis, but he was not at the meeting either, Gutierrez said.

 In attendance were Lazaro Gonzalez, one of his attorneys, and several Immigration and Naturalization Service officials. The doctors were psychiatrists Dr. Jerry Wiener and Dr. Paulina F. Kernberg, and a psychologist, Dr. Lourdes Rigual-Lynch, all affiliated with top northeastern medical schools and hospitals.

 Manny Diaz, the Miami family lawyer who attended the meeting, said there was no clear outcome. Diaz said no further meetings have been scheduled with the INS.

 ''It was just a quick meeting to exchange ideas,'' Diaz said. ''There was just a lot of discussion about the welfare of the child, no specific conclusion.''

 DISAPPOINTED

 But a source familiar with the talks said government officials were disappointed by what they regard as Lazaro Gonzalez's stubborn refusal to discuss ways to transfer Elian to his father with a minimum of trauma.

 ''The government once again bent over backwards to accommodate the relatives by agreeing to move the meeting, but Lazaro remained very unwilling to discuss a neutral location for the transfer,'' a source familiar with the talks said. ''He was adamant it happen at his house.

 ''We sincerely believe that Elian needs to see his primary caregivers are supporting him in this, and they're just not willing to do it.''

 One government official said authorities would likely ask that Elian be brought to a neutral location in Florida to be turned over either to Juan Miguel or to a third party. A more remote possibility would be to ask the Miami relatives to bring him to his father, who flew to Washington, D.C., last week.

 If the great-uncle refuses to obey the government's instructions for a hand-over, U.S. immigration authorities have said they will seek a court order forcing him to surrender Elian. Continued defiance could mean criminal contempt of court charges and arrest.

 As a last resort, government officials say they are prepared to send in federal agents to take custody of the boy so he can be reunited with his father. The government has said the father is free to return to Cuba with Elian immediately upon regaining physical custody.

 ADDITIONAL VISAS?

 In Washington, meanwhile, the State Department indicated it might approve some of the additional 22 visas requested by the Cuban government as a ''support team'' for Elian's father -- its condition for Juan Miguel Gonzalez's remaining in Washington while court appeals in the case are wound up.

 In a last-ditch appeal to stave off Elian's return to Cuba, Miami Mayor Joe Carollo said he and Miami-Dade County Mayor Alex Penelas will fly to Washington this morning to meet with U.S. Attorney General Janet Reno. Carollo said they will ask Reno to establish a ''transition period of about 30 days'' to lessen any risk of trauma to the boy.

 Even as the government and Lazaro Gonzalez haggled over the meeting Monday, it quickly became apparent that the relatives planned to continue to fight.

 ''We are actively considering several legal remedies to prevent removal of Elian to Cuba,'' said Kendall Coffey, one of the team's attorneys.

 On Monday, just minutes before deadline, the relatives' legal team filed legal arguments at the 11th Circuit Court of Appeals in Atlanta, which will hear the family's challenge of a federal court ruling last month that upheld the government's authority to send Elian home.

 Barring an emergency order prohibiting the government from going ahead, Reno has said she is not bound to await the outcome of the appeal.

 Herald staff translator Renato Perez, Herald writer Mireidy Fernandez, and Herald wire services contributed to this report.