BOGOTA (Reuters) - The United States targeted Venezuela’s government with new sanctions on Monday and called on allies to freeze the assets of its state-owned oil company PDVSA after deadly violence blocked humanitarian aid from reaching the country over the weekend.

As Colombia’s foreign minister warned about “credible threats to the life” of Venezuela’s opposition leader Juan Guaido, the Trump administration also took its pressure campaign to the United Nations Security Council, asking it to discuss the situation in Venezuela, diplomats said.

The U.S. Treasury Department’s sanctions were imposed on four Venezuelan state governors allied with the government of President Nicolas Maduro, blocking any assets they control in the United States.

The new sanctions were announced in Bogota as U.S. Vice President Mike Pence and Guaido met with members of the Lima Group, a bloc of nations from Argentina to Canada dedicated to peaceful resolution of the political and economic crisis in Venezuela.

Pence said the United States would stand by Guaido until freedom was restored. He called for all Lima Group nations to immediately freeze PDVSA’s assets and to transfer ownership of Venezuelan assets in their countries from Maduro’s “henchmen” to Guaido’s government-in-waiting.

He also said tougher measures were coming against the OPEC member.

“In the days ahead ... the United States will announce even stronger sanctions on the regime’s corrupt financial networks,” Pence said. “We will work with all of you to find every last dollar that they stole and work to return it to Venezuela.”

While the day presented a united regional front against Maduro, who is widely accused of coming to power through fraudulent elections, there was no clear sign that the latest measures would succeed in pushing him toward the exit.

‘CREDIBLE THREATS’

On a day that began with Guaido urging “all options” to be considered to remove Maduro, the threat of military intervention seemed if anything weaker after the meeting.

Guaido, sitting next to Pence at the meeting, asked for a moment of silence for those killed in what he called the “massacre” of the weekend.

Guaido himself could be in danger from the Maduro regime, Colombian Foreign Minister Carlos Holmes Trujillo said, speaking on behalf of the Lima Group.

“There’s information about serious and credible threats to the life and integrity of Juan Guaido and his family, as well as to his wife’s family. From Bogotá, we want to hold the usurper Maduro responsible for any violent action against Guaido, against his wife and against their relatives,”

At least three people were killed and almost 300 wounded during protests and clashes on Saturday as U.S.-backed aid convoys attempted to enter Venezuela to deliver food and medicine.

In a joint statement at the close of the meeting, the Lima Group said Maduro was a threat to peace and security in the region and called for his immediate exit, a democratic transition and free elections.

Guaido, recognized by most Western nations as Venezuela’s legitimate leader, has urged the bloc to consider “all options” in ousting Maduro.

But the Lima Group said it “reiterates the conviction that the transition to democracy must be conducted by the Venezuelans themselves peacefully and within the framework of the Constitution and international law,” the statement said.

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CALL FOR AMNESTY

Pence repeated an earlier statement that there would be an amnesty for members of the armed forces who throw their support behind Guaido. He said he hoped Maduro and those supported by his “corruption and his brutality” will leave Venezuela peacefully.

“We make clear to them that we will support the interim president’s call for amnesty, an inclusive government, an inclusive future for members of the armed forces, who have laid down their arms and stand with the Guaido government,” Pence said.

Unlike the Lima Group, of which the United States is not a member, the Trump administration has so far declined to rule out the use of military force. But Peruvian Deputy Foreign Minister Hugo de Zela Martinez denied there was any division in the group over the use of force.

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Pence also called for Mexico and Uruguay, two-left leaning regional governments, to join most of the region’s other powers in embracing Guaido as Venezuela’s rightful president.

“We believe there can be no bystanders, no one on the sidelines of this, particularly in our hemisphere,” Pence said.

Washington wants the 15-member U.N. Security Council to formally call for free, fair and credible presidential elections with international observers. Russia, which along with China has major investments in Venezuela’s energy sector and back Maduro, proposed a rival draft resolution.

Soldiers and armed groups loyal to Maduro blocked a convoy of trucks with food and medicines during the weekend. Maduro says the aid efforts are part of a U.S.-orchestrated coup.

At least 167 members of Maduro’s armed forces have deserted since Saturday and more are expected to flee across the border to Colombia.

In the Venezuelan town of San Antonio, near the border with Colombia, residents on Monday chafed at the continued border closure ordered by Maduro’s government last week. Four people have been killed, 58 have suffered bullet wounds and at least 32 arrested since Friday, local rights group Penal Forum said.

Residents increasingly cross into the neighboring country to work and buy basic goods that are unavailable in Venezuela, which has suffered years of hyperinflation and shortages of food and medicine. Illegal crossings over back roads known as “trochas” generally require paying tolls to low-level criminals who control them, known as “trocheros.”

“We were hungry when before the border closed. Now it will be even worse,” said Belkis Garcia, 34, walking with her husband along a trail that leads to Colombia. “We have to pay (to cross), so the little money we have for half the food is not enough. We don’t know what will happen if the border continues closed.”

The Lima Group said it would ask the International Criminal Court to consider “the serious humanitarian situation in Venezuela, the criminal violence of Nicolas Maduro’s regime against the civilian population, and the denial of access to international assistance.”