CARACAS/WASHINGTON (Reuters) - Venezuelan President Nicolas Maduro’s government stepped up a legal battle against efforts to oust him on Thursday, while the opposition said the international community had pledged more than $100 million in humanitarian aid for the country.

Venezuelans line up as they wait for a free lunch at the "Divina Providencia" migrant shelter outskirts of Cucuta, on the Colombian-Venezuelan border, Colombia February 13, 2019. REUTERS/Edgard Garrido

Venezuela’s opposition, which argues Maduro’s presidency is illegitimate because he won in a sham vote, is trying to wrest control of the OPEC nation’s oil sector from him and deliver aid to a population suffering food and medicine shortages.

Maduro says this is part of a strategy to carry out a U.S.-backed coup and has vowed to remain in office, despite around 50 nations recognizing opposition leader Juan Guaido as president. Maduro retains the backing of key allies Russia and China as well as control of Venezuelan state institutions including the military.

Venezuela’s chief state prosecutor, Tarek Saab, said on Thursday his office had opened an investigation into new opposition-appointed directors at state-run oil firm PDVSA and its U.S. refiner Citgo, Venezuela’s most valuable foreign asset.

The pro-Maduro Supreme Court then ruled that the proposed board members were prohibited from leaving the country. At least some of the people are believed to already be outside Venezuela.

Saab said Guaido had “grotesquely made circus-style appointments” in order to please foreign interests and destabilize the country.

“The only directors legitimately appointed to the boards of PDVSA and its subsidiaries are those ... who have been appointed by the executive,” Saab said, according to his office’s Twitter account.

As head of the National Assembly, Guaido invoked constitutional provisions last month to assume the interim presidency.

The transitional government should include members of the ruling “Chavismo” movement and military leadership, in an effort to guarantee stability for new elections, a top opposition lawmaker said.

That interim government would have 13 months to hold fresh presidential elections from the date Maduro officially steps down as president, Stalin Gonzalez, the second vice president of the congress, told Reuters.

“We need to give space to sectors of Chavismo that are not Maduro because we need political stability,” Gonzalez said in an interview.

The opposition, made up of a coalition of parties, plans to hold primaries in order to put forward a sole candidate for the presidential elections, he added. Chavismo is the movement founded by former President Hugo Chavez, who Maduro succeeded following Chavez’ death in 2013 from cancer.

“THOUSANDS OF WINDOWS”

Guaido’s U.S. representative, Carlos Vecchio, spoke to an aid conference on Thursday hosted at the Organization of American States (OAS) headquarters in Washington, to urge the international community to help get assistance into Venezuela.

Vecchio and his aides estimated they had received pledges of more than $100 million in humanitarian assistance from the United States and others, including previous commitments as well as new ones made at the conference.

“We must open thousands of windows to bring humanitarian aid to Venezuela,” Vecchio told the conference, which was attended by diplomats and representatives from dozens of countries.

Elliott Abrams, Washington’s special representative on Venezuela, said the United States was looking for ways to send in aid as he reiterated U.S. support for Guaido.

“I can assure you that there will be more U.S. assistance coming in the future,” Abrams said, without giving specifics.

Guaido has said humanitarian aid will enter the country on Feb. 23, setting the stage for a showdown with Maduro, who has said it is not needed and should not be let in.

Guaido’s declaration was “absolutely absurd” as he had “control of nothing,” Venezuelan Foreign Minister Jorge Arreaza said on Thursday.

“In Venezuela there’s only one government – the government of President Maduro - so no one can give deadlines, especially this man,” Arreaza told reporters at the United Nations.

The administration of U.S. President Donald Trump has said it wants a peaceful resolution to the crisis but has refused to rule out military intervention. Cuba accused the United States on Thursday of moving special forces closer to Venezuela as part of a covert plan to intervene.

Military aircraft from the United States had flown to strategically located Caribbean islands last week, Cuba said.

“It’s a new lie,” Abrams said, when asked about it at the Washington event.