A key group of European powers delivered a diplomatic blow to embattled Venezuelan President Nicolas Maduro by publically endorsing opposition leader Juan Guaido as the country's legitimate interim president Monday.

The act by Spain, Germany, France and Britain added to the pressure on Maduro after he defiantly rejected the EU’s Sunday deadline to call a new presidential election. Sweden, Denmark, Austria, the Netherlands and Lithuania also lined up behind Guaido, who also has the backing of the United States and many South American nations.

TOP VENEZUELA GENERAL REJECTS MADURO'S LEGITIMACY, THROWS SUPPORT BEHIND INTERIM PRESIDENT

"We are working for the return of full democracy in Venezuela: human rights, elections, and no more political prisoners," Spanish Prime Minister Pedro Sanchez said in a televised announcement. "The international community has a duty to help and ensure that this happens with the necessary guarantees.”

Meanwhile, French President Emmanuel Macron said Venezuelans have the right to “express themselves freely and democratically.”

The European countries are urging Guaido to hold free and fair elections as soon as possible.

VENEZUELA’S OPPOSITION LEADER COURTS MADURO’S INTERNATIONAL ALLIES AFTER ‘CLANDESTINE MEETINGS’ WITH MILITARY

The 35-year-old lawmaker, who is the head of the South American country’s National Assembly, declared himself Venezuela’s interim head of state last month, directly challenging Maduro’s claim to the presidency. He says the constitution allows him to assume power temporarily when the president is deemed illegitimate.

Since then, he has been courting the international community – including Maduro’s staunchest supporters, Russia and China – as well as Venezuela’s military leaders.

Pressure is mounting on Maduro to step down just a month after he began his second term as president following disputed and controversial 2018 elections.

However, Maduro is not showing any signs of caving, even as he grows more isolated internationally and lashes out at the EU and the Trump administration, which has imposed billions in sanctions on Venezuela’s oil exports and demanded Maduro’s departure.

VENEZUELA'S LADY MACBETH? MADURO'S 'PUPPET MASTER' WIFE IS A LAWYER, TV STAR, STYLE ICON - AND LINKED TO DRUG TRAFFICKING

“I don’t accept ultimatums from anybody,” Maduro told Spanish TV channel La Sexta in an interview broadcast late Sunday. “Why should the EU be giving ultimatums to a country?”

He added: “No, international politics can't be based on ultimatums. That was the era of empires and colonies."

Maduro then continued his accusations against the Trump administration, which he claims is preparing a coup and that “the military option is on [President] Donald Trump’s table.”

“The United States wants to return to the 20th century of military coups, subordinate puppet governments and the looting of resources,” he said, adding Trump would leave the White House “stained with blood” if there is a military intervention.

Maduro has rejected a U.S.-backed effort to send emergency food and medicine into Venezuela.

“We are not beggars,” he said on Venezuelan state TV.

CLICK HERE TO GET THE FOX NEWS APP

Meanwhile, Russia slammed the statements by the European leaders, accusing them of interfering in Venezuela’s affairs and attempting to “legitimize usurped power.”

The Associated Press contributed to this report.