"They use sledgehammers instead of boxing gloves", President Maduro said, accusing the United States of seeking his removal so that it could take control of Venezuela's vast oil reserves.
In an interview with Spanish journalist Jordi Évole, Venezuela's president cited the Bible and past United States military debacles in an attempt to dissuade Washington from taking military action against Caracas.
Guaido issued the call in a surprise appearance via video link to the gathering of Lima Group members and several other partners, including the United States and European partners in Ottawa.
The Venezuelan leader, accused of running the OPEC nation of 30 million people like a dictatorship and wrecking its economy, has defied them and said European rulers are sycophantically following President Donald Trump.
"We warn Prime Minister Justin Trudeau against playing any role in bringing about regime change in another country".
Two opposition rivals with a good chance of winning were barred from standing, while food handouts and other subsidies to hungry Venezuelans were linked with political support.More news: Cancer awareness event to show benefits of exercise after diagnosis
"We are faced with arbitrary rule, without respect for the guarantees laid down in the Constitution or the highest principles of the dignity of the people", they said.
But the socialist leader showed no signs of caving in and lashed out at the European Union and the Trump administration, which has also put pressure on the Venezuelan government by imposing sanctions on Venezuelan oil exports and demanding Maduro's departure.
But he stopped short of breaking off diplomatic relations with the 16 European countries that recognized his rival Monday, unlike his swift move to cut off ties with the USA after it threw its support behind Guaido last month.
Long-time backers Russian Federation and China are among at least nine nations that have declared their support for Maduro. But there were no signs the armed forces were turning against Maduro.
In an interview that aired Monday with Italy's Sky TG24 he said that he had written Pope Francis asking for help in fostering dialogue with the opposition.More news: STREAM: Puppy Bowl 2019
Such intervention "does not contribute in any way to a peaceful, effective and vital settlement to the crisis that Venezuelans are enduring", Kremlin spokesman Dmitry Peskov said in comments carried by state news agency TASS. Eleven of its members have recognised Guaido.
On Monday, Guaido said the European Union needed "to act in unison so that the forces, who are still supporting Maduro feel all the weight of Europe's diplomatic and political pressure". It aims to facilitate dialogue and is due to hold its first meeting in Uruguay on Thursday. "You will leave the presidency stained with blood", Maduro said Sunday evening in an interview with the Spanish television station Sexta.
The 35-year-old Guaido, accused by Maduro's government of staging a US -directed coup, has galvanized Venezuela's opposition with a hopeful message.
The statement adds that Trudeau "commended Juan Guaido for his courage and leadership in helping to return democracy to Venezuela and offered Canada's continued support". "Their support for us has been fundamental", he said.
"They are trying to corner us with ultimatums to force us into an extreme situation of confrontation", Maduro said.
Under Maduro's stewardship, oil-dependent Venezuela has lurched into an economic crisis that has left the country suffering from hyperinflation and shortages of food and medicine.More news: Northwest measles outbreak revives debate over vaccine laws