Caracas, Venezuela (CNN) Embattled Venezuelan President Nicolas Maduro has refused to accept an ultimatum from European countries calling for free elections.

Last week, the United Kingdom, France, Germany and Spain gave Maduro until Sunday to call new elections or they would recognize the country's self-declared interim president Juan Guaido as president.

"We don't accept ultimatums from anyone," Maduro said in an interview with Spanish private channel LaSexta on Sunday. "It's as if I went to the EU and said, 'I give you seven days to recognize the republic of Catalonia or if not, we will take measures.' No, no. International politics cannot base itself on ultimatums. That is the epoch of imperialism or colonies."

Maduro went on to question why the European Union should dictate political norms to his country.

"Why does the European Union tell a country in the world that already had presidential elections in accordance to its constitution, its laws, its institutions, with the international observers, that they have to repeat their presidential elections? Why? Because their right allies in Venezuela didn't win," he said.

Maduro also refused to accept the humanitarian crisis in his country.

"Venezuela does not have a humanitarian crisis. Venezuela has a political crisis. Venezuela has an economic crisis. We have a huge economic war!" he said.

As Maduro shows no willingness to relinquish power amid defections and calls for his ouster, Guaido outlined an opposition road map Sunday.

The main points of Guaido's plan concern humanitarian aid and Venezuela's assets.

Maduro's critics claim he has ushered the once-wealthy oil nation into economic collapse and a humanitarian disaster. The crisis is only exacerbated by his alleged refusal to permit aid into the country, despite a shortage of food and medicine, they say.

In a series of tweets Sunday, Guaido laid out the three steps to his road map:

Create a coalition of national and international interests to facilitate humanitarian aid to three collection points;

Demand the military permit aid into the country;

Ask Europe to protect Venezuela's assets abroad.

Guaido said Saturday that humanitarian aid would be sent to collection points in Cucuta, Colombia; Brazil and an unspecified Caribbean island.

Photos: In photos: Venezuela in crisis Supporters of Venezuelan opposition leader Juan Guaido wave a Venezuelan flag as they wait for him to make an appearance in the country's capital of Caracas on Monday, March 4. Hide Caption 1 of 47 Photos: In photos: Venezuela in crisis Guaido greets supporters upon arriving at a Caracas airport on March 4. He crossed the border to Colombia in late February before embarking on a South American tour, meeting the presidents of Colombia, Brazil, Paraguay and Ecuador, along with US Vice President Mike Pence. By doing so, Guaido ignored a travel ban imposed on him by the country's Supreme Court. Hide Caption 2 of 47 Photos: In photos: Venezuela in crisis Guaido shakes hands with Pence in Bogota, Colombia, on Monday, February 25. The room was filled with humanitarian aid destined for Venezuela. Guaido's wife, Fabiana Rosales, is pictured at left. Hide Caption 3 of 47 Photos: In photos: Venezuela in crisis Demonstrators clash with Venezuelan soldiers at the Simon Bolivar International Bridge in Cucuta, Colombia, on Saturday, February 23. Hide Caption 4 of 47 Photos: In photos: Venezuela in crisis Supporters of President Maduro take part in a march in Caracas on February 23. Hide Caption 5 of 47 Photos: In photos: Venezuela in crisis Guaido supporters take part in a march in Caracas on February 23. Venezuelan security forces fired tear gas and rubber bullets to disperse a crowd demanding to cross the Venezuela-Colombia border, which was ordered closed by Maduro. Hide Caption 6 of 47 Photos: In photos: Venezuela in crisis Demonstrators push a bus that was set on fire during clashes with the Venezuelan National Guard in Urena, Venezuela, on February 23. Hide Caption 7 of 47 Photos: In photos: Venezuela in crisis Maduro waves the national flag during a pro-government march in Caracas on February 23. During the rally at the Venezuelan capital, Maduro told supporters he is breaking all diplomatic relations with Colombia and is calling for its ambassadors and consuls to leave Venezuela. Maduro recently began a second term after a 2018 vote that his political opposition and many in the international community denounced as a sham. Hide Caption 8 of 47 Photos: In photos: Venezuela in crisis People attempt to salvage packages from a truck loaded with humanitarian aid after it was set ablaze on a bridge between Cucuta, Colombia, and Urena, Venezuela, on February 23. Hide Caption 9 of 47 Photos: In photos: Venezuela in crisis Venezuelan opposition supporters protested in Caracas on Tuesday, February 12, calling on Maduro to let humanitarian aid into the economically crippled country. Hide Caption 10 of 47 Photos: In photos: Venezuela in crisis Guaido addresses the crowd in Caracas on February 12. Hide Caption 11 of 47 Photos: In photos: Venezuela in crisis A man wearing a Venezuelan flag sits on a traffic light during the demonstration in Caracas on February 12. Hide Caption 12 of 47 Photos: In photos: Venezuela in crisis Guaido waves to supporters during the rally in Caracas on February 2. Hide Caption 13 of 47 Photos: In photos: Venezuela in crisis An anti-government protester wears glasses with a Venezuelan flag motif at the demonstration in Caracas on February 2. Hide Caption 14 of 47 Photos: In photos: Venezuela in crisis Protesters gather for the Caracas rally on February 2. Hide Caption 15 of 47 Photos: In photos: Venezuela in crisis Maduro supporters gather in Caracas on February 2. Hide Caption 16 of 47 Photos: In photos: Venezuela in crisis Opposition demonstrators protest against Maduro's government on Wednesday, January 30. Hide Caption 17 of 47 Photos: In photos: Venezuela in crisis In this handout photo released by the Miraflores Presidential Press Office, Maduro flashes a "V for victory" hand gesture after arriving at the Fort Tiuna military base in Caracas on January 30. Hide Caption 18 of 47 Photos: In photos: Venezuela in crisis Members of the National Police line up to guard the entrance of Venezuela's Central University in Caracas during an anti-government protest on January 30. Hide Caption 19 of 47 Photos: In photos: Venezuela in crisis Guaido speaks to reporters in Caracas on January 30. The United States and more than a dozen other countries have recognized Guaido as Venezuela's legitimate ruler. Hide Caption 20 of 47 Photos: In photos: Venezuela in crisis A Maduro mural is seen in the Petare slum of Caracas on Tuesday, January 29. Hide Caption 21 of 47 Photos: In photos: Venezuela in crisis Guaido listens to deputy Rafael Veloz during a session at the National Assembly in Caracas on January 29. The Assembly met to debate a legal framework for creating a transitional government and calling new elections. Simultaneously, Venezuela's attorney general asked the Supreme Court to freeze Guaido's assets and bar him from leaving the country. Hide Caption 22 of 47 Photos: In photos: Venezuela in crisis A view of the National Assembly building in Caracas on January 29. Hide Caption 23 of 47 Photos: In photos: Venezuela in crisis The president of Venezuela's Supreme Court, Maikel Moreno, speaks at a news conference in Caracas on January 29. Hide Caption 24 of 47 Photos: In photos: Venezuela in crisis A man pumps fuel at a gas station in Caracas on January 29. A day earlier, the United States announced sanctions against Venezuela's state oil company, Petroleos de Venezuela, S.A. Hide Caption 25 of 47 Photos: In photos: Venezuela in crisis Supporters of Venezuela's opposition hold up letters that read "Justice" at a rally to hear Guaido speak in Caracas on Saturday, January 26. Hide Caption 26 of 47 Photos: In photos: Venezuela in crisis Guaido speaks to reporters after attending Mass in Caracas on Sunday, January 27. Hide Caption 27 of 47 Photos: In photos: Venezuela in crisis Government supporters in Caracas hold a rally in support of Maduro on January 26. Hide Caption 28 of 47 Photos: In photos: Venezuela in crisis Maduro holds a news conference in Caracas on Friday, January 25. The Venezuelan strongman has accused Guaido and the United States of trying to orchestrate a coup against him. Hide Caption 29 of 47 Photos: In photos: Venezuela in crisis Portraits of former Venezuelan leaders Simon Bolivar and Hugo Chavez hover in the background as Venezuelan Defense Minister Vladimir Padrino Lopez, bottom left, addresses a news conference in Caracas on Thursday, January 24. Venezuela's top military officials swore their allegiance to Maduro after other nations recognized Guaido as head of state. Hide Caption 30 of 47 Photos: In photos: Venezuela in crisis A man wrapped in a Venezuelan flag raises his arms in front of security forces during anti-government protests in Caracas on Wednesday, January 23. Hide Caption 31 of 47 Photos: In photos: Venezuela in crisis Opposition supporters in Caracas protest Maduro on January 23. Hide Caption 32 of 47 Photos: In photos: Venezuela in crisis Opposition supporters react to tear gas as they take part in the Caracas rally on January 23. Sporadic clashes erupted, but Maduro's military response to the protests seemed more measured than in the past. Hide Caption 33 of 47 Photos: In photos: Venezuela in crisis Police secure an area in Caracas on January 23. Hide Caption 34 of 47 Photos: In photos: Venezuela in crisis A National Police officer fires rubber bullets in Caracas. Hide Caption 35 of 47 Photos: In photos: Venezuela in crisis People raise their hands to show solidarity with Guaido, who was declaring himself interim president on January 23. Hide Caption 36 of 47 Photos: In photos: Venezuela in crisis A wounded protester in Caracas on January 23. Hide Caption 37 of 47 Photos: In photos: Venezuela in crisis Security forces stand in a street full of stones after clashing with demonstrators in Caracas. Hide Caption 38 of 47 Photos: In photos: Venezuela in crisis Maduro, speaking to a crowd of supporters at the Miraflores Palace in Caracas, holds up a document that says his government is breaking off diplomatic ties with the United States. "We cannot accept the invasive policies of the empire, the United States, the policies of Donald Trump," he said to cheers from the crowd on January 23. "Venezuela is a land of liberators." Hide Caption 39 of 47 Photos: In photos: Venezuela in crisis A wounded protester shows his back as riot police clashed with opposition demonstrators in Caracas on January 23. Hide Caption 40 of 47 Photos: In photos: Venezuela in crisis A man walks by a bus that had been set on fire in Caracas. Hide Caption 41 of 47 Photos: In photos: Venezuela in crisis An opposition demonstrator runs with a tear-gas canister on January 23. Hide Caption 42 of 47 Photos: In photos: Venezuela in crisis Guaido greets a crowd in Caracas on January 23. Hide Caption 43 of 47 Photos: In photos: Venezuela in crisis Protesters set up barricades to block a road in Caracas. Hide Caption 44 of 47 Photos: In photos: Venezuela in crisis A National Police officer fires tear gas at demonstrators in Caracas while another shoots the scene with a cell phone. Hide Caption 45 of 47 Photos: In photos: Venezuela in crisis Demonstrators in Caracas protest Maduro's government. Hide Caption 46 of 47 Photos: In photos: Venezuela in crisis Venezuelan banknotes were thrown on the ground during the Maduro protests on January 23. Hide Caption 47 of 47

Previously, Guaido has accused Maduro loyalists of attempting to sell off Venezuela's foreign gold reserves in an attempt to move them to the beleaguered nation's central bank. He has pleaded with British officials to halt the transactions , saying any wealth transferred "will be used by the illegitimate and kleptocratic regime."

The European Union -- whose parliament, along with the United States and several Latin American countries, has recognized Guaido's interim leadership -- is scheduled to co-host a meeting to "create conditions for a political and peaceful process to emerge."

The International Contact Group on Venezuela will meet in Montevideo, the Uruguayan capital, on Thursday. It seeks "free, transparent and credible elections." The group includes Bolivia, Costa Rica, Ecuador, France, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, the United Kingdom and co-host Uruguay.

Dueling protests

US President Donald Trump told CBS on Sunday that American military action remains an option in Venezuela, the day after Maduro appealed for militia members and young people to join the armed forces ahead of this month's military exercises, which he called the most important in the country's history.

"We are preparing to defend the sacred motherland," he told supporters, "in case they one day dare to mess with our beloved Venezuela."

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Guaido, too, saw his supporters take to the streets en masse in Caracas to support his claim to power. Last month Guaido, who heads the opposition National Assembly, invoked a constitutional rule in challenging Maduro's presidency.

"We are going to meet again in the street to show our gratitude to the support that the European Parliament has given us, to continue insisting on the entry of humanitarian aid and to continue our path toward freedom," Guaido tweeted Saturday.

Meanwhile, pro-Maduro marches commemorated the 20th anniversary of the inauguration of Maduro's mentor and predecessor, the late Hugo Chavez

Assuring his supporters that "there will not be a dictatorship in Venezuela" and reiterating his call for dialogue, Maduro said the pro-government Constitutional Assembly is studying the possibility of early parliamentary elections "this very year."

Juan Guaido waves to supporters as he leaves a Saturday rally in Caracas.

Yet he remained resistant to national and international calls that Venezuela hold presidential elections. Maduro was re-elected to the presidency in May, in elections that the United States and several Latin American countries did not recognize as legitimate. He began a second six-year term last month.

"I am the president of the Bolivarian republic of Venezuela, and I owe myself to everyone, not just some of them. I owe myself to all of Venezuela. Sovereign president, acting president, the workers' president, the president of the people, President Maduro, Chavista President!" he declared.

Do defections reveal cracks in veneer?

Maduro has suffered a pair of defections that some observers say are indicative of his fleeting grip on power.

In a video, a man identifying himself as Jonathan Velasco, the Venezuelan ambassador to Iraq, declared his support for Guaido, whom he praised for being on the "right side of history, the people and the constitution."

Nicolas Maduro's supporters also took to Caracas' streets to defend his presidency Saturday.

Another on-camera statement came Saturday from a man introducing himself as Gen. Esteban Yanez Rodriguez, the head of strategic planning for Venezuela's air force. Explaining he was part of the air force's high command, the man said he was defecting from Maduro's military and backing Guaido.

He also said that "90% of the armed forces" stand against Maduro and "to continue ordering the armed forces to repress the people is to have more dying of hunger and illness."

The latter defection -- which follows that of Venezuela's military attaché in Washington, Col. Jose Luis Silva Silva -- is particularly important as observers have said the military will be key to any effort to force new presidential elections.

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Venezuela's air force command reacted to the defection on Twitter, calling Yanez a "traitor."

"Worthless is the man of war who betrays the loyalty and fidelity swearing of the land of Bolivar and the legacy of Comandante Hugo Chavez, and kneels before the imperialist pretensions," its tweet said.