The US has upgraded Malaysia in its annual report on human trafficking on Monday (27 July) despite calls by human rights groups and nearly 180 US lawmakers to maintain the country's standing on the list of worst offenders for failing to suppress trafficking.

Cuba was also upgraded from its lowest rank for the first time since it was included in the US State Department's annual Trafficking in Persons report in 2003. Saudi Arabia was also upgraded from the lowest Tier 3 rank.

Reuters said that South Sudan, Burundi, Belize, Belarus and Comoros were also downgraded to the lowest rank. Thailand remains in the lowest rank, Tier 3 for the second straight year, together with Iran, North Korea and Zimbabwe.

Egypt was downgraded to the Tier 2 Watch List after failing to increase anti-trafficking efforts, the report says.

The news agency notes that Malaysia's upgrade paves the way for the 12-nation Trans Pacific Partnership or TPP which prohibits deals with Tier 3 countries. The legislation which was approved by Congress in June, gives US President Barack Obama expanded trade negotiating powers.

A total of 160 US House of Representatives and 18 US Senators wrote to the US Secretary of State John Kerry, urging him to keep Malaysia on the Tier 3 list, saying that there was no justification for the upgrade and questioning whether the upgrade was a bid to keep Malaysia in the TPP.

The State Department confirmed on Monday that although Malaysia did not fully meet the minimum standards to eliminate human trafficking, it was making significant efforts to do so. The Southeast Asia nation has bolstered its anti-trafficking laws and more than doubled trafficking investigations.

The Department also said that trafficking convictions in the 12 months to March fell to three from nine in the previous year and the report also described conditions under which migrants are still forced into labour and women and children are coerced into the sex trade.

Kerry is expected to visit Malaysia, the current chair of the 10-bloc Association of Southeast Asian Nations or better known as ASEAN.

In its upgrade of Cuba to the Tier 2 Watch List, the report said the country was making "significant efforts" to comply with the minimum standards for the elimination of trafficking including sharing data, improving cooperation, and offering services to trafficking victims.

The Department report said that there remained reports of forced labour in the government-backed overseas work missions that send 51,000 workers to more than 67 countries but that the Ministry of Labour and Social Security had taken a lead role in combating sexual violence and sex trafficking.

Uzbekistan was upgraded to Tier 2 Watch List from Tier 3, following a government decree prohibiting forced child labour in the 2014 cotton harvest and new fines against college directors and farms for using child labour.

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