HAVANA -- A long-awaited undersea fiber-optic cable linking Cuba with the outside world arrived on the island on Wednesday, promising a bandwidth bonanza for a country saddled with exorbitant telephone rates and among the slowest Internet connection speeds on the planet.

The cable connecting Cuba with key ally Venezuela was brought ashore in the eastern resort of Siboney in a ceremony attended by dignitaries from the two countries, the state-run Prensa Latina news agency reported.

The cable is not expected to be operational until the summer, but its arrival is a landmark for an island that often feels cut off from the outside world, 52 years after Fidel Castro's revolution turned it from decadent American playground to crumbling Soviet satellite.

When finished, the cable is expected to increase Internet speed 3,000-fold and be capable of handling about 80 million simultaneous phone calls.

That's good news in a country where Web pages open at the speed of molasses oozing out of a jar. A recent report by Akamai Technologies Inc. said Cuba has the second slowest Internet speed in the world, besting only the tiny Indian Ocean-island chain of Mayotte.

And that's for those lucky enough to have online access.

A report last year by Cuba's National Statistics Office said only 2.9 percent of the population had used the Internet over a 12-month period, most through work or school - the lowest level of Internet penetration in the Western Hemisphere.

Deputy Information Minister Jorge Luis Perdomo told reporters at a technology conference this week that, for now at least, Cubans would continue to be able to connect solely through their jobs or through school.

He said the limitations were not the result of any political concern over what increased connectivity will mean, but rather a product of the sorry infrastructure on the island and the time it will take to improve it.

Still, widespread Internet activity is sure to be a wild card on an island with a state-controlled media, a closed political system and where opposition groups are often marginalized or worse.

Last week a video began circulating on blogs - including one maintained by well-known activist Yoani Sanchez - that appears to show an Interior Ministry official warning a group of government employees that Cuba's enemies hope to use the Internet to attack the island.

"We are not 'fighting' new technology," the official says. "But we must understand it, use it in our interest, and know what our enemy means to do with it."

The official repeatedly brings up the case of Alan Gross, a 61-year-old American subcontractor detained in Cuba since December 2009 on suspicion of spying. Washington has said he was distributing communication equipment to the Jewish community. Cuban prosecutors are seeking a 20-year jail term.

The man in the video, who was not identified, said Gross was carrying satellite phones and technology that would have created unauthorized Internet networks.

"Technology in itself is not a threat," the man says. "The threat is what is done, or what can be done, using technology."

Cuba has had no reaction to the video, nor has it confirmed its authenticity.

The fiber-optic cable project is being carried out by Alcatel-Lucent SA of Paris for the state telecommunications companies of Cuba and Venezuela. Cuban officials have said it is expected to cost about $70 million, and be functional in June or July. A second segment will extend from Cuba to nearby Jamaica.

Cuba relies on slow, expensive satellite links because the U.S. government's 48-year embargo has prevented most trade between the island and the United States and has made companies in other countries shy away from doing business with Cuba.

Cubans have high hopes for the cable, despite warnings that things will not change quickly.

"I think it is fantastic," said Lazaro More, a musician who twice a week goes to a Havana "cybercafe" that allows access to a limited number of internal Web sites and e-mail options. He spends $3 for two hours of service, a fortune for many since Cubans earn an average of just $20 a month.

"I am sure this will make it a lot easier for Cubans to communicate with the rest of the world," he said.