GUATEMALA CITY (Reuters) - Hundreds of peasant farmers and indigenous Maya blocked a major highway in Guatemala’s western highlands on Monday, demanding that President Jimmy Morales reverse a policy aimed at forcing a U.N.-backed anti-graft unit to leave the country.

FILE PHOTO: Guatemala's President Jimmy Morales delivers a message at the National Palace of Culture in Guatemala City, Guatemala September 6, 2018, 2018. REUTERS/Luis Echeverria

Groups representing the protesters said in a statement they planned more rallies over the next two days, including in capital Guatemala City, after Morales announced at the end of August that he would not renew the mandate of the International Commission Against Impunity in Guatemala (CICIG).

Although CICIG can operate in Guatemala until the end of next year, Morales’ government applied further pressure last week by prohibiting Ivan Velasquez, the head of the investigative unit, from returning to Guatemala, for reasons of “public security.”

Morales’ predecessor is in prison and standing trial for running a customs racket uncovered by CICIG. Last year, the commission started investigating the current president’s family for alleged corruption and supported an impeachment of Morales.

Morales, a former comedian elected in 2015, denies any wrongdoing and says the CICIG has overstepped its remit.

Protesters in the western highlands town of Solola brandished placards demanding Morales resign, broadcast images showed.

“We believe the leadership of commissioner Velasquez is important for the fight against corruption,” said protester Josue Chavajay by phone.

“Guatemala has changed, it is not the same as it was three years ago (when Morales was elected),” said Chavajay.

The CICIG was formed in 2006 to help Guatemalan prosecutors break a cycle of impunity that helped organized crime penetrate government in the Central American country, and it is credited with improving the justice system.

Morales’ decision to end the body’s charter in Guatemala was heavily criticized by the United Nations and European countries.

The U.S. Senate Committee on Foreign Relations also questioned the move in a letter to U.S. Secretary of State Mike Pompeo on Friday, pointing out that U.S.-donated military vehicles had appeared near the CICIG headquarters and the U.S. embassy on the day of the announcement by Morales, who spoke while flanked by soldiers.

The deployment of the vehicles “appeared intended to send a political message,” said the letter, calling the move “unacceptable.”

Guatemala had a series of military governments in the 1970s and 1980s, and the military remains influential in politics.

The U.S. State Department, which has backed the CICIG in the past, has been more ambiguous in its comments. Pompeo called Morales last week and expressed “continued support for a reformed CICIG,” spokeswoman Heather Nauert said on Thursday.

U.S. funding is important for the CICIG. Morales has been one of the few world leaders to back U.S. President Donald Trump’s recognition of Jerusalem as Israel’s capital by shifting the Guatemalan embassy in Israel to Jerusalem.

On Monday, the head of the U.N. human rights office, former Chilean President Michelle Bachelet, said the decisions to end the CICIG mandate and block Velasquez were “deplorable.”

Last week, the Guatemalan government asked U.N. Secretary General Antonio Guterres not to interfere in the country’s affairs after he expressed concern about the decisions.