CARACAS (Reuters) - The runner-up in Venezuela’s election, which was widely condemned by other countries as undemocratic, will formally challenge his loss to President Nicolas Maduro after refusing to recognize the result, his campaign said on Wednesday.

Ballots are counted on a table at a polling station during the presidential election in Caracas, Venezuela, May 20, 2018. REUTERS/Marco Bello

The head of Henri Falcon’s campaign, Claudio Fermin, told a news conference that given reports of hundreds of irregularities in Sunday’s voting, they would challenge the results before the national electoral board during the next 20 days.

“There is a whole collection of irregularities,” Fermin said.

Electoral board chief Tibisay Lucena, who is on individual U.S. and European Union sanctions lists, has already said Falcon’s allegations of voter fraud lacked evidence.

The United States, European Union and most major Latin American nations have all said the election, which Maduro won easily, did not meet democratic standards. Venezuela’s mainstream opposition boycotted the election because two of its most popular leaders were barred, authorities had banned several political parties, and the election board is run by Maduro loyalists.

Maduro, the 55-year-old successor to late leftist leader Hugo Chavez, hailed his win, with 68 percent of the vote, as a victory against “imperialism.”

Fermin said the government had failed to comply with the electoral board’s requirement that so-called “red points,” set up by Maduro’s government to register which Venezuelans receiving state aid had voted, be at least 200 meters from polling centers.

Some red points were as close as 5 meters from voting centers, he said. Reuters witnesses on Sunday saw red points set up even inside some voting centers.

Fermin also said in some voting centers Falcon’s observers were barred from entering and other centers stayed open later than 6 p.m., when they were required to close. Still, turnout was under 50 percent, well below the 80 percent reached in previous elections.

In response to Maduro’s re-election, U.S. President Donald Trump on Monday ramped up sanctions against OPEC member Venezuela, which is mired in an economic crisis that has led to shortages of basic goods. Maduro on Tuesday ordered the expulsion of two top U.S. diplomats in Caracas in retaliation.

The expulsions would be “met with a swift response” from Washington, U.S. Vice President Mike Pence said on Wednesday, although he gave no details.