US-Cuban relations have fallen to their lowest point since Barack Obama became US president and are in danger of getting worse unless the two countries take serious steps toward ending five decades of hostility, according to Cuba experts.

After a brief warming last year, both countries appear to be falling back into old, antagonistic ways, obscuring whatever progress that has been made and hindering further advances, the experts said this week.

“The past year has proven that when it comes to US-Cuba relations, old habits die hard,” said Dan Erikson of the Inter-American Dialogue think tank in Washington.

Obama, who took office in January 2009 and has said he wanted to recast US-Cuban relations, lifted restrictions on travel by Cuban Americans to the communist-ruled island and initiated talks on migration issues and direct postal service.

Since then, Cuban Americans have flooded the island and the two longtime ideological foes have held their first high-level discussions in years. But recent developments have been mostly negative.

Cuba jailed US contractor Alan Gross in December on suspicion of spying and continues to hold him without charges.

Cuba’s government has been condemned internationally for its treatment of opponents, including imprisoned dissident Orlando Zapata Tamayo, who died in February from a hunger strike, and the “Ladies in White,” wives and mothers of imprisoned dissidents, were shouted down by government supporters during protest marches this month.

Obama rebuked the Cuban government in a strongly worded statement on March 24, saying Cuba continues “to respond to the aspirations of the Cuban people with a clenched fist.”

US officials think they have done enough to elicit a more positive response from Cuba, while Cuba complains that Obama has done too little.

Miami attorney Timothy Ashby, a former US Commerce Department official in charge of trade with Cuba, said neither has done what is necessary to overcome 50 years of bitterness.

“Neither government is willing to take a significant step that would serve as a demonstration of genuine goodwill,” he said.

Both nations have taken actions that have not helped the fragile improvement begun by Obama.

Obama angered the Cuban government in November when he responded to questions via email from dissident Cuban blogger Yoani Sanchez, who Cuban leaders view as at least complicit with their enemies in Europe and the United States.

In February, Assistant Secretary of State Craig Kelly provoked a bitter Cuban reaction when he met with dissidents following migration talks with Cuban officials in Havana.

Cuba, in turn, has soured the political climate by harshly criticizing Obama for his lack of action while taking little of its own.

Its detention of Gross, which US officials say Cuba has refused to discuss, has called into question its desire for change even among those who want better relations.

In a letter last week to Cuba’s top diplomat in Washington, 41 members of the US House of Representatives said the detention of Gross “has caused many to doubt your government’s expressed desire to improve relations with the United States.”

“We cannot assist in that regard while Mr Gross is detained in a Cuban prison,” said the legislators, who included sponsors of pending legislation to end a US ban on travel to Cuba.

The United States has said Gross was in Cuba to expand Internet services for Jewish groups, but conceded he entered the island on a tourist visa that would not permit such work.

His work was funded under US programs aimed at promoting democracy in Cuba, which Cuban leaders view as part of a long US campaign to topple their government.

US officials are saying behind the scenes that there will be no more initiatives with Cuba until Gross is released.

Domestic political concerns are among the reasons cited for the lack of US-Cuban progress, with Obama mindful of possible criticism from conservatives for moving too quickly and Cuban President Raul Castro dealing with anti-US hardliners while he tries to fix Cuba’s weak economy.

“Sadly, there are reactionary forces on either side of the Florida Straits,” Ashby said.

The United States could move rapprochement along by removing Cuba from its list of nations considered state sponsors of terrorism, a designation that has long angered Cuba, Ashby said.

At the same time, Cuba must release Gross either outright or, if necessary, on something like parole if it insists on putting him on trial, according to John McAuliff of the New York-based Fund for Reconciliation and Development, which promotes better relations between the two countries.

Western diplomats in Havana also said Cuba must treat its dissidents better, saying another death would be a serious blow to relations with both the United States and Europe.