Despite the headline-grabbing rapprochement between Washington and Havana, which culminated in yet another meeting between Presidents Barack Obama and Raúl Castro last month, trade with the Communist island has not picked up in the way U.S. officials expected.

The Obama administration last month announced the most significant loosening of sanctions against Cuba in decades, but U.S. government officials say they now depend on Havana's help to more readily work with American businesses, The Washington Post reported.

But as long as the decades-old U.S. embargo against Cuba is still technically in place, Cuban leaders have shown little appetite to sign contracts with American companies, a development the administration had hoped would help overcome opposition to lifting the economic sanctions.

The full removal of the embargo also depends on democratic reforms Castro may not be willing to make, but unnamed U.S. officials told The Washington Post that proponents of further relaxation in Congress are "desperate" for gestures from the Cuban government.

But U.S. Commerce Secretary Penny Pritzker, who this week became the first such official to visit Cuba in 65 years, acknowledged the continuing difficulties in eliminating trade barriers with the country.

"There is much we in the United States do not fully understand about the Cuban economic system," she said. "I'm here because we need to develop relationships with each other and start to learn from one another."

Nevertheless, Pritzker assured her Cuban counterparts that Obama remained committed in his effort to eventually do away with the embargo, the Associated Press noted. 

"The president wants to see the embargo lifted, but the president realizes it will take time," she said.

In the meantime, Pritzker suggested, it was up to the Cuban regime to make significant changes. 

"We urge President Castro and his government to make it easier for Cuban citizens to trade and travel more freely, to enjoy the fruits of their labor, to access the Internet and to [be] hired directly by foreign companies," she added.