The latest round of talks between U.S. and Cuban negotiators ended after just one day on Tuesday, and participants did not disclose how much progress they had made in their attempt to restore diplomatic relations between Havana and Washington, Reuters reported.

Assistant U.S. Secretary of State Roberta Jacobson on Sunday had traveled to the Cuban capital to meet with Josefina Vidal, the Cuban foreign ministry's chief of U.S. affairs, beginning Monday. Initially, the negotiations had been expected to last for a few days, the news service added.

Cuba's foreign ministry announced the completion of the talks in a statement.

"At the end of the meeting, which took place in a professional climate, the two delegations agreed to maintain communication in the future as part of this process," the ministry noted.

The rapprochement took place in a climate of tensions as the United States and Cuba last week had been at the center of a public disagreement over Venezuela, Agence France-Presse recalled.

Even as Jacobson arrived in Havana, thousands of people attended a concert and rally to "support the Bolivarian people and government" after the Cuban government pledged its "unconditional support" to embattled Venezuelan leader Nicolás Maduro, AFP added.

Cuban leader Raúl Castro traveled to Venezuela on Tuesday to attend a summit of leftist Latin American governments known as the "ALBA bloc," Reuters said. The meeting was called on short notice after President Barack Obama had declared Caracas a threat to its national security and imposed sanctions on seven high-ranking Venezuelan officials.

Unlike during the two prior rounds of talks the two delegations had held in January and February, reporters were excluded from Monday's discussions, Voice of America noted. The diplomats wanted to keep the discussions "lower key," according to U.S. State Department spokeswoman Jen Psaki.

"Their focus is on rolling up their sleeves and having tough discussions, and getting the work done," Psaki told reporters in Washington.

The United States and Cuba had severed diplomatic ties in 1961. In December, Obama and Castro jointly announced that the two countries would seek to normalize relations.