Cuba is expanding its intelligence operations in the Middle East and South Asia to keep a closer eye on U.S. military operations there, according to a former top Defense Intelligence Agency official.

Chris Simmons, a former DIA counterintelligence Cuba analyst, said Havana has placed top intelligence operatives in key embassy postings in countries such as Iran, Turkey and Pakistan to gather information for Cuba’s own defenses and provide intelligence to America's enemies.

"Havana has an insatiable appetite for information about U.S. military operations as well as U.S. intelligence operations," Simmons told FOXNews.com. "They see it as a requirement for protecting the regime."

Cuba has sent "ambassador spies" — intelligence chiefs-turned-diplomatic envoys — to regions where the United States has active military operations, Simmons said. Before adopting this strategy, Cuba placed such people in the United States.

One of these is Gustavo Machin Gomez, who heads the Cuban mission in Pakistan. He was one of 14 Cuban diplomats expelled from the United States on espionage charges in 2003.

Another, Ernesto Gomez Abascal, Cuba’s ambassador to Turkey, was either an intelligence agent or an intelligence collaborator who was Cuba’s ambassador to Iraq before the fall of Saddam Hussein's regime, according to Simmons.

Cuba's increased relations with Pakistan and Iran offer other signs of its expanding spy network, Simmons said. In 2006, Havana reopened its embassy in Pakistan after 16 years, and Iran and Cuba are believed to be working together to jam U.S. radio and TV programming into Iran.

"I think that it’s very clear that Cuba is opening up another front in the war with the United States," said Roger Noriega, former assistant secretary of state for Western Hemisphere affairs from 2003 to 2005.

"That’s the Cuban revolution’s primary occupation and preoccupation," Noriega added.

For decades, Castro's spies have successfully monitored activities at America's domestic air and naval bases, which allowed them to anticipate every major U.S. military deployment, from the 1983 invasion of Grenada to the beginning of Operation Iraqi Freedom in 2003, Simmons said.

Cuban intelligence has "whipped the asses of American intelligence for decades," Noriega said. He warned that Cuba could be brokering "intelligence information to firm up political support or just help out their friends, be they terrorist organizations or just hostile governments."

Cuba's new strategy follows a series of intelligence setbacks that forced the Castro regime to re-think the way it monitors U.S. military movements. Those included the closing of a Cuban intelligence center in Canada, the 2003 expulsion of several Cuban diplomats working in Washington and the arrest of one-time DIA Cuba analyst Ana Montes, who for more than a decade was believed to be passing U.S. secrets to the Castro government.

It's believed that some of those secrets were passed on to Russia, China and Iran.

Some experts have expressed doubt that Cuban diplomats with former intelligence ties in these and other countries are, in fact, spying on their host countries. "Ambassadors usually don’t go spooking around," said Larry Birns, director of the Washington, D.C.-based Council on Hemispheric Affairs.

Pentagon officials and the DIA refused comment on Simmons’ assessment of Cuba’s spying practices. "We are always concerned about the safety of our military members abroad," said a DIA official who requested anonymity.

Several attempts to contact Cuban officials at the country’s interest section in Washington were unsuccessful. But Simmons, who founded the Cuban Intelligence Research Center in Leesburg, Va., said Cuba's far-reaching spy network — with more than 11,500 agents, including some 3,500 focused on foreign operations — is a concern.

He said the Castro government could be providing Iran with its knowledge of U.S. military capabilities, at a price. "Historically, in the Castro regime, when it comes to intelligence sharing, nothing is free," Simmons said.

U.S. lawmakers are calling for greater attention to be paid to Cuba’s diplomats and their activities. Rep. Lincoln-Diaz Balart, R-Fla., said "insufficient attention" was being given to threats of potential links between Cuba and state sponsors of terrorism such as Iran. He spoke following a recent briefing Simmons gave to Republican members of the House Foreign Affairs Committee.

Said Simmons: "The Cubans have a front-row seat and everyone is too busy to pay attention to what they are doing."