WASHINGTON (AP) _ The U.S. immigration service today ordered Elian Gonzalez's Florida relatives to make him available Wednesday for a meeting with his grandmothers at a neutral site.

In a letter to the lawyers for the boy's uncle, Lazaro Gonzalez, the immigration service made compliance with the order a condition of Elian's immigration status.

Meantime, support grew on Capitol Hill for legislation to grant U.S. citizenship to the boy, as his grandmothers met with lawmakers today and tearfully pleaded for his return to Cuba.

``He belongs in Cuba,'' Mariela Quintana, the paternal grandmother, told reporters. ``He was born in Cuba and he's a Cuban citizen.''

President Clinton left open the possibility of a veto of any citizenship bill. ``I have not decided what to do and I would not rule that out,'' he told reporters.

The immigration service stressed that its order to produce the boy for meeting at the Miami Beach home of Barry University President Jeanne O'Laughlin, who is a sister in the Dominican order, ``is only a visit and will not change Elian's present placement in the case of Lazaro Gonzalez.''

The letter sign by Michael A. Pearson, executive associate immigration commissioner for field operations, said, ``In order to ensure that Elian has the chance to spend time alone with his grandmothers, the INS is obliged to direct Lazaro Gonzalez to make Elian available for a visit with his grandmothers on Wednesday at 4:00 p.m.''

Pearson said O'Laughlin's home is in a gated area where security can be assured. ``This site is an appropriate neutral location that would permit a private meeting,'' Pearson wrote.

The order came after Lazaro refused on Monday to agree to a meeting at any sight other than his own home, Pearson wrote.

Pearson said religious leaders not associated with the National Council of Churches, which has been escorting the grandmothers in this country, offered to make church property available for a meeting Monday, but Lazaro Gonzalez refused. He would not propose a neutral sight himself and turned down a personal telephone appeal from the grandmothers to hold the meeting at the home of Lazaro Gonzalez's brother, Pearson wrote.

``Again, Lazaro Gonzalez made clear to the grandmothers that his home was the only site at which he would allow them to visit Elian,'' Pearson wrote.

``In light of the rift in the family that the recent events have caused, as well as security and publicity concerns, the grandmothers have clearly stated that they would not be comfortable visiting with their grandson in Lazaro Gonzalez's home,'' Pearson added.

On Capitol Hill today, Raquel Rodriquez, Elian's maternal grandmother, fighting back tears, said she hoped ``to stop the possibility of granting citizenship to the child, for it would be more painful'' to his Cuban family.

The grandmothers spoke with reporters, through an interpreter, after meetings with Reps. Sheila Jackson Lee, D-Texas, and James McGovern, D-Mass. ``I see no reason for legislation to give Elian citizenship at this time,'' Jackson said. She urged Clinton to work to oppose the measure, even if it means a veto.

The two grandmothers were to meet later in the day with other lawmakers sympathetic to pleas for the boy's return to his father in Cuba.

In Havana, the Cuban government said in a lengthy statement published by the Communist Party daily Granma that the U.S. attorney general's office was seeking a court order requiring the Miami relatives to turn Elian over for a meeting with his grandmothers.

But no action was filed in court today and in Washington, Justice spokeswoman Carole Florman responded, ``We can't comment on what we might or might not do'' to arrange a meeting between the grandmothers and the boy. But Attorney General Janet Reno was meeting with aides on the issue in her office today.

The president, meanwhile, urged Congress to delay action until the issue had played out in court, and he urged lawmakers and others involved to think first about ``what is right for the child.''

``No one can really know for sure, I suppose, what terrible and probably not fully conscious burdens that child has already sustained because he lost his mother,'' Clinton said, adding that the competition over young Elian also was likely affecting him.

The grandmothers' meeting with Jackson Lee had been delayed by a January snowstorm that shut down much of the capital.

``It's the first time they've seen snow,'' said the Rev. Joan Brown Campbell of the National Council of Churches, which sponsored the grandmothers' trip. ``They wanted to know if they could go out and touch it.''

Campbell said the women feared that if the legislation in Congress passed ``that they may not see him in his young years back in Cuba.''

Versions of the citizenship bill were introduced Monday in both the House and the Senate, and Senate Majority Leader Trent Lott, R-Miss., told his colleagues they might debate the measure as early as Wednesday. A vote Wednesday is possible, but both sides said they doubt final action will occur until next week at the earliest.

In the House, rival but unbinding legislation was introduced urging that Elian be repatriated with his father in Cuba.

``It is time to put an end to his ordeal by reuniting him with his family and his grandparents in Cuba,'' said Rep. Charles Rangel, D-N.Y., senior Democrat on the House Judiciary Committee.

Leaders of both parties struggled to find a consensus, which did not exist Monday, as lawmakers returned to work from their long winter break.

Both parties scheduled meetings today to discuss the issue.

The two women flew here on Monday night by private jet after their attempt to visit the boy in Miami failed. The boy's maternal grandmother, Raquel Rodriguez, and paternal grandmother, Mariela Quintana, shunned an invitation to have dinner Monday night at the home of Elian's relatives in Miami, who insisted the meeting take place there. The grandmothers wanted to meet privately with Elian at a neutral site.

Some of Elian's Miami relatives were planning to travel to Washington as well.

Lott and a group of Florida lawmakers put in motion the process to bestow citizenship on the boy, who has been cared for by the Miami relatives since he was found clinging to an inner tube off the Florida coast on Nov. 25. His mother and 10 other Cubans died in their ill-fated attempt to reach the United States.

Sponsors hoped to whisk the citizenship bill through Congress quickly, largely to remove the case from jurisdiction of the Immigration and Naturalization Service, which has ruled that the boy should be returned to his father on the island. Passage of the citizenship legislation also would render moot a federal court appeal of the INS ruling by Elian's great-uncle in Miami, sponsors said.

``This moves the decision-making out of the hands of the INS and into the hands of the (state) courts,'' said Sen. Connie Mack, R-Fla., the measure's chief Senate sponsor.

Sen. Patrick Leahy of Vermont, the Senate Judiciary Committee's top Democrat, denounced the bill.

``For the Congress to grant citizenship to a young boy over the father's objection makes a mockery of family values and it hands Castro yet another reason to portray the United States as the enemy,'' Leahy said. Cuban President Fidel Castro's government has sponsored a series of mass demonstrations demanding the boy's repatriation.

Bestowing American citizenship is a power Congress uses rarely.

It gave citizenship to Winston Churchill and Mother Teresa and posthumously to Raoul Wallenberg, a Swedish diplomat who saved tens of thousands of Hungarian Jews in World War II.