CARACAS (Reuters) - Venezuela’s President Nicolas Maduro, excluded from the Summit of the Americas due to regional censure of his democratic record, mocked the meeting in Lima as a “complete failure” on Saturday.

Venezuela's President Nicolas Maduro (C) waves during a ceremony with militia members in Caracas, Venezuela April 13, 2018. Miraflores Palace/Handout via REUTERS

Addressing red-shirted supporters at an “anti-imperialist” rally in Caracas, Venezuela’s socialist leader said other Latin American presidents were wasting their time criticizing him.

“Everyone who attacks Venezuela ends up losing,” he said “The Summit of the Americas has been a complete failure.”

U.S. President Donald Trump’s last-minute cancellation weakened the summit’s importance, then overnight western air strikes on Syria overshadowed it.

Even so, opposition to Maduro’s autocratic government around Latin America is strong, with various leaders viewing an upcoming May 20 presidential election as a farce intended to legitimize his rule. Authorities have banned the two most popular opposition leaders from running for election.

“I was seeing reports of some empty speeches by right-wing, unpopular, murderous, imperialist lackey presidents,” Maduro told the rally. “It’s shameful seeing those presidents, hated by their peoples, speak about Venezuela’s noble people.”

Maduro, 55, who is being targeted by Washington with sanctions due to accusations of corruption and rights abuses, condemned as a “criminal act” the air strikes on Syria over a suspected poison gas attack.

“Violating international law, they launched missiles to inflict panic and terrorism on Syrians and destroy scientific centers,” he said. “There has been powerful global revulsion around the planet.”

Standing in for Trump at the Lima summit, U.S. Vice President Mike Pence told regional leaders on Saturday that more must be done to isolate Maduro, and Washington would not stand “idly by” as the country crumbles.

Pence also said Russia was spreading misinformation about the U.S. missile attacks on Syria.