WASHINGTON (Reuters) - Two U.S. senators called on the U.S. Department of Justice on Wednesday to investigate allegations of drug trafficking by senior officials in the government of Venezuelan President Nicolas Maduro, as the country struggles with economic crisis.

FILE PHOTO: Venezuela's Vice President Tareck El Aissami talks to the media during a news conference in Caracas, Venezuela November 17, 2017. REUTERS/Marco Bello

In a letter to U.S. Attorney General Jeff Sessions seen by Reuters, Republican Senator Marco Rubio and Democrat Robert Menendez said they were concerned about possible connections between Maduro’s government and drug trafficking organizations and wanted an investigation “in order to better understand the nexus between criminal actors and members of Maduro’s inner circle.”

Despite being a major oil producing country, Venezuela is undergoing a severe economic and social crisis, with millions suffering food and medicine shortages, hyperinflation and growing insecurity.

Rubio is chairman of the Senate Foreign Relations Committee’s western hemisphere subcommittee, and Menendez is its ranking Democrat. Both lawmakers are vocal critics of the Venezuelan government.

In their letter, they raised concerns that the situation in Venezuela could destabilize the region.

The Venezuelan Information Ministry did not immediately respond to a request for comment. In the past, Maduro has dismissed accusations about drug trafficking links as a smear campaign by Washington, adding that the United States is to blame for the drug trade because it is such a large market for illegal narcotics.

On Aug. 1, 2016, a U.S. District Court announced the indictment of Nestor Reverol, who is now Venezuela’s interior minister, on charges of participating in an international cocaine trafficking conspiracy. In February 2017, the U.S. Treasury Department imposed sanctions against Venezuelan Vice President Tareck el-Aissami for drug trafficking and other related crimes.

And in December 2017, two nephews of Maduro’s wife, Franqui Francisco Flores de Freitas and Efrain Antonio Campo Flores, were convicted in U.S. federal court for drug smuggling.

The European Union announced new sanctions on several senior Venezuelan officials, including Reverol, on Monday, saying this was an expression of the bloc’s concern with the political crisis under Maduro.

Rubio and Menendez also asked Sessions to support efforts by the Organization of American States to address human rights concerns in Venezuela.

A Justice Department spokeswoman said the letter had been received and was being reviewed, but declined further comment.