UPDATE 1-EU stresses support for Cuba even as U.S. hikes sanctions

(Adds meeting with president; paragraphs 4,7)

HAVANA, Sept 9 (Reuters) - The European Union is committed to helping Cuba develop its economy, EU foreign policy chief Federica Mogherini said on Monday, during a three-day trip to Havana, even as the United States hikes sanctions on the Communist-run island.

The EU started normalizing relations with one-party Cuba about the same time as the United States five years ago, ending decades of Cold War-era hostility.

But EU and U.S. policies have diverged, as U.S. President Donald Trump has unraveled the detente pursued by his predecessor. He has reverted to seeking to coerce the government to reform, a strategy that many experts say has long failed.

"The EU is Cuba's top commercial partner and investor, and we have tripled cooperation in the last two years," Mogherini, the EU high representative for foreign affairs and security policy, told a news conference with Cuban Foreign Minister Bruno Rodriguez.

EU development aid is welcome in an ailing economy - one of the world's last Soviet-style command economies - struggling with tighter U.S. sanctions and lower aid from leftist ally Venezuela in the wake of its own economic and political crisis.

Last week, the United States issued new regulations limiting the remittances its citizens can send to Cuba.

Europe could help Cuba update its economy, said Mogherini, who also met Cuban President Miguel Diaz-Canel on Monday. Investment would also help European companies consolidate their foothold on the island as it opens up.

The official said the two countries already held bilateral talks on topics such as sustainable development and human rights within the framework of a political dialogue and cooperation pact agreed in 2017.

"We have also continued the dialogue on the situation in the region and cooperation, on Venezuela in particular," she said.

Cuba is a strong ally of leftist President Nicolas Maduro, whom most Western nations want to step down in favor of opposition leader Juan Guaido, arguing his election was fraudulent and there must be a new vote.

Several opposition groups have called for the EU to suspend its cooperation agreement with Cuba, due to what the groups call an increase in repression on the one-party island.

They accuse authorities of raiding dozens of activists' homes in recent weeks and detaining more than 100 people last weekend alone.

Cuban authorities dismiss dissidents, who have limited support on the island, as a tiny minority of provocateurs financed by the United States to subvert the government.

EU officials say they believe they can better influence Cuba on human rights through dialogue than coercion. (Reporting by Nelson Acosta Writing by Sarah Marsh; Editing by Cynthia Osterman)