The National Election Council announced with more than 92 per cent of polling stations reporting that Mr Maduro had won nearly 68 per cent of the votes, beating his nearest challenger Henri Falcon by more than 40 points.
The verdict means Mr Maduro has won re-election for another six-year term.
As the results were being announced, residents of downtown Caracas banged on pots and pans in protest. Mr Falcon accused the government of buying votes and dirty tricks to boost turnout amongst poor voters mostly hurt by widespread food shortages and hyper-inflation in what was once Latin America’s wealthiest nation.
UK Foreign Secretary Boris Johnson also condemned the elections in Venezuela, which he described as “deeply flawed”.
Mr Johnson, who is on a five-day tour of Latin America, said the polls were “neither free nor fair”.
“I am disappointed, but not surprised, that Maduro pressed ahead with deeply flawed elections to secure his own survival,” Mr Johnson said. He added: “The condemnation of the international community is loud and clear.
“We shall work closely with our EU and regional partners in the coming weeks to determine how we can continue to support a political resolution.
“I remain deeply concerned by the man-made humanitarian and economic crisis, which is growing worse by the day.
“I urge the Venezuelan government to take immediate action and let the international community deliver essential food and medicines. The suffering of ordinary Venezuelan people cannot be allowed to continue.”
The disputed victory is likely to heighten international pressure on Mr Maduro. Even as voting was taking place on Sunday, a senior US official said the Trump administration might press ahead on threats of imposing crippling oil sanctions and Secretary of State Mike Pompeo warned “sham elections change nothing”. Mr Falcon was joined in his demand for a new election by third-place finisher Javier Bertucci, who won around 11 per cent of the vote.
Mr Bertucci, a TV evangelist who handed out soup at his campaign rallies, stopped short of challenging the results, partly blaming what he called a mistaken opposition boycott that led to a turnout of around 46 per cent – the lowest in a presidential race in two decades of revolution.
But he said he nonetheless favours a new election soon and urged Mr Maduro to do the courageous thing and desist from running. If Mr Maduro presses forward, he warned, Venezuela would explode before his new six-year term was scheduled to start in January.
A social crisis years in the making has worsened as Venezuela’s oil production – the source of almost all of its foreign income – has collapsed to the lowest level in decades and financial sanctions by the Trump administration has made it impossible for the government to renegotiate debts.
More than one million people have fled the country in the past two years and 14,000 per cent inflation has crushed the minimum wage to less than £1.49 a month.
Mr Maduro, 55, immediately called for dialogue with his opponents and put the best face forward on what analysts said were nonetheless disappointing results underscoring how vulnerable his hold on power remains.
Despite energetic campaigning, his overall vote haul slipped by 1.6 million from 2013 when he was first elected after predecessor Hugo Chavez’s death from cancer.