Sen. Marco Rubio criticized the State Department for treating Cuba, China and Thailand too leniently in its 2016 Trafficking in Persons Report, an annual look at forced prostitution, childhood slavery and other abuse around the world.
The State Department places every country in one of three tiers based on its governments efforts to comply with "the minimum standards for the elimination of trafficking," as spelled out in the Victims of Trafficking and Violence Protection Act.
Congress first passed that legislation, and President Bill Clinton signed it into law, in 2000, and lawmakers have reauthorized it four times since then. It requires the State Department to evaluate all nations, including the United States, in annual reports to Congress.
"When we talk about human trafficking, we're talking about slavery -- modern-day slavery that still today claims more than 20 million victims at any given time," Secretary of State John Kerry told ambassadors, trafficking victims and other guests Thursday during a State Department ceremony marking the release of the new annual report.
Kerry said he had personally made many phone calls to foreign ministers, presidents and other leaders to push them to combat human trafficking.
In its report last year, the State Department moved Cuba up from Tier 3, the worst level, to Tier 2, and kept Cuba at Tier 2 in the current report.
"(It's) a ranking not justified by the facts on the ground, but rather reflective of the Obama administration's pursuit of normalized relations with the Castro regime at any cost," Rubio said after the report's release.
The United States and Cuba re-established diplomatic ties in July 2015 after a 54-year break grounded in the Cold War.
Kerry said the rankings of Cuba and other countries "don't take into account political and other factors."
In its section on Cuba, the new State Department report concludes: "The government of Cuba does not fully meet the minimum standards for the elimination of trafficking; however, it is making significant efforts to do so."
The Cuban government prosecuted 18 sex traffickers in 2014, the most recent year for which data was available, and released a report on its anti-trafficking efforts last October.
"The Cuban government was more transparent in providing details of anti-trafficking efforts and the government's overseas (forced) medical missions program," the State Department said. "However, the government did not prohibit forced labor, report efforts to prevent forced labor or recognize forced labor as a possible issue affecting its nationals in medical missions abroad."
Noting that the government is the primary employer in Cuba, the State Department said 84,000 Cubans work overseas on medical missions.
"Some participants in foreign medical missions and other sources allege (that) Cuban officials force or coerce participation in the program," the report said. "However, the Cuban government and some participants say the program is voluntary and well paid compared to jobs within Cuba."
The State Department used similar broad language to justify China's Tier 2 ranking, saying it has significant trafficking problems but is "making significant efforts" to meet minimum standards for its elimination.
Rubio criticized that ranking.
"While the internal State Department deliberations for this year's report are not yet known, there is no indication that China's trafficking track record has improved," the Miami Republican said.
The report acknowledged: "State-sponsored forced labor continues to be an area of significant concern in China."
While the government closed most "Re-education Through Labor" camps last year, it continues to use forced labor at government rehabilitation and detention centers, the report said.
"Chinese women and girls are subjected to sex trafficking within China," the State Department found. "
The United States was one of 36 countries that received a Tier 1 ranking, along with most European nations. Israel was the only Middle East country to get the top grade, while Taiwan, South Korea and the Philippines were the only Asian nations.
The full State Department report can be read here.