BY LAURA FIGUEROA

A 2008 state law aimed at increasing regulation on agencies selling trips to Cuba could make it harder for those seeking to book flights from South Florida, an attorney for the U.S. Justice Department said Friday in Miami federal court.

The argument comes amid heightened speculation that President Barack Obama could soon lift remaining travel restrictions for Cuban Americans looking to visit loved ones on the island.

''They are unconstitutional and preempted by federal law,'' said Michelle R. Bennett, an attorney for the U.S. Justice Department, referring to requirements passed by the legislature last year that increased the amount of bond money and registration fees agencies specializing in trips to Cuba have to pay.

The state law, which requires the agencies to post up to a $250,000 bond and pay up to $2,500 in registration fees, is at the center of a lawsuit filed in July against the state by more than a dozen local travel agency owners. They say the requirements are part of a ''witch hunt'' aimed at driving them out of business.

U.S. District Court Judge Alan S. Gold said he will return next week with a final ruling.

During the hearing Gold questioned attorneys on both sides of the issue about how the increased requirements would play into recent relaxation of travel restrictions to Cuba.

Cuban exiles can now travel to the island once every year and stay as long as they like, a move that overturned a Bush administration policy that limited travel to once every three years.

There have been widespread reports that Obama will announce lifting the remaining restrictions on Cuban family travel and remittances to coincide with next week's Fifth Summit of the Americas in Port of Spain, Trinidad.

Bennett said Florida's law would make it more difficult for Floridians to travel to Cuba ``if there are less agencies to sell the trips.''

Attorneys for the state countered that it was ''too premature'' to determine if the state law would in fact drive the agencies out of business, because the temporary injunction prevented the state from enacting the new set of regulations.

''We can't know what effect it's going to have because when you entered the injunction you stopped the ability to set the rules,'' Jonathan Glogau, an attorney for the state told Gold. ``We're just assuming the worst at this point.''

Bennett's presentation on behalf of the federal government comes on the heels of a report from the U.S Justice department that called Florida's measure intrusive.

The 35-page review said that Rivera's law interfered ``with the federal government's ability to speak for the United States with one voice in foreign affairs.''

Local travel agents said they are ''optimistic'' that the report, coupled with Bennett's arguments on behalf of the Justice Department, can help convince Gold to rule in their favor.

''We already feel as though we have won,'' said Armando García, owner of Marazul Charter Travels, one of the agencies involved in the suit. 'The Federal government is basically saying what we've been telling the state all along -- `we are already regulated heavily by the federal government.' ''

State Rep. David Rivera, who sponsored the measure, brushed off the Justice department report, passing it off as the Obama administration being ``only interested in kissing up to the Castro regime rather than protecting Florida consumers from the abuses of these travel agencies.''

During the 2008 state Legislative session the Cuban American lawmaker touted his measure as being a ''homeland security'' issue, because it targeted Florida based agencies that sold trips to the countries on the U.S. State Department's list of nations that sponsor terrorism.

This Legislative session Rivera continues to press the issue of travel to Cuba. He has introduced a clause to the state's education budget that prohibits the use of state funds for academic trips to the island.

''Even if there are any judicial setbacks, I am ready to fight for this issue until my last legislative breath,'' said Rivera, who was present at the court hearing.