BY LESLEY CLARK AND FRANCES ROBLES

As a couple accused of spying for Cuba head to federal court Wednesday, Cuba watchers say the latest case of espionage could crimp the Obama administration's efforts to renew talks with the government in Havana.

The arrests last week of former State Department employee Walter Kendall Myers and his wife, Gwendolyn Steingraber Myers, came as the Cuban government agreed to an overture by the U.S. State Department to resume long-suspended discussions on migration and direct mail between the two countries.

But with some critics of the regime opposed to renewing the talks until Cuba has shown some democratic change, analysts suggest momentum could slow.

Sen. Mel Martinez said Tuesday he might send a letter to President Barack Obama asking for a briefing on ``this issue, as well as counterintelligence efforts in regards to Cuba.''

'RECURRING THEME'

''This is a very disturbing, recurring theme,'' the Florida Republican said. "This is a government that very aggressively goes after intelligence information in our country and I think it affects our broader relationship with Cuba.''

Martinez suggested the administration should postpone the talks between diplomats, saying "we don't know how those talks could have been compromised by what has been disclosed to the Cubans. I think it would be foolish for us to be in negotiations with one arm tied behind our back.''

The U.S. State Department has said it wants to reopen the talks -- suspended by the Bush administration in 2004 -- to 'reaffirm both sides' commitment to safe, legal and orderly migration.''

''This case should not have an impact on the talks, but it will,'' said Wayne Smith, a former head of the U.S. Interests Section in Havana who advocates normal relations between the two countries.

'You already have people like Sen. Mel Martinez saying, 'We can't trust these guys. We have to be very, very careful.' Well of course you have to be careful! They have their intelligence operations, and we have ours. This case will cause interruptions, cause heartburn and cause Washington to move slowly.''

State Department spokeswoman Heide Bronke declined to comment on the case.

A senior U.S. official said Washington had not yet scheduled a time or place for the migration talks, which traditionally were held twice a year.

It is unclear, the official said, whether the Myers case will affect the scheduling of new talks.

''The approach the president has laid out on Cuba is based on our interests and values. These will be the determining factors,'' the official said, requesting anonymity because the case is still under investigation. "When it is in our interest to proceed, we will do so.''

Many experts stress that it is no surprise that Cuba, with one of the world's most sophisticated intelligence operations, has spies throughout the United States -- including on the federal government payroll.

''The United States does the same thing with countries we classify as a terrorist state -- I expect there are hundreds of others out there,'' said Joe Garcia, a board member of the Cuban American National Foundation. "This is just an excuse for the fearful not to take action.''

Garcia and Smith agreed that it was unlikely that Myers -- who last worked as a European analyst for the State Department's Bureau of Intelligence and Research and taught at John Hopkins University -- knew any secrets that would compromise national security.

''This is not James Bond,'' Garcia said. "This is Maxwell Smart.''

A U.S. official said of potential talks with the Cuban government: "We go into this with our eyes open.''

Chris Simmons, a veteran spy catcher and former Defense Intelligence Agency analyst, said Cuba is among the most voracious intelligence gatherers in the world and often sells the information to other countries.

''Kendall Myers is a perfect example of the undeniability of Cuba's intelligence trafficking,'' Simmons said. "From a what's-in-it-for-Cuba standpoint, he might offer little, but combine that with his access to European analysis and students at John Hopkins, he would have served as an intelligence link.''

DETENTION HEARING

The Myerses, who pleaded not guilty last week to charges of conspiracy and serving as clandestine agents, are due to appear at a detention hearing Wednesday. U.S. District Magistrate John M. Facciola is to determine whether the couple -- being held in jail without bail -- should remain behind bars.

They face more than 30 years in jail, and federal prosecutors are seeking the return of Myers' State Department income and the couple's retirement savings.