Vice President Mike Pence heads to Colombia, Argentina, Chile and Panama on Sunday, meeting with foreign leaders in a role that is becoming familiar for an administration that has left many top diplomatic posts unfilled.
Since April, Pence has visited South Korea, Japan, Indonesia and Australia, attended security meetings in Munich and Brussels, and traveled to Estonia, Georgia and Montenegro.
Vice presidents frequently travel abroad to meet with foreign leaders, but Pence's role comes at a time of intense foreign interest in U.S. policy. President Donald Trump has embraced overturning much of his predecessor's legacy, and it has frequently fallen on Pence to explain those changes to foreign leaders.
Pence has reassured U.S. allies nervous about tweets and statements by Trump — "statements that were mixed about our commitment to NATO," said scholar of the vice presidency Joel Goldstein of Saint Louis University School of Law. Pence has assured allies of the "continuing [U.S.] commitment," Goldstein noted.
South and Central America
Pence's latest foray will take him to South and Central America, where Goldstein says the vice president can play a helpful role because many senior State Department positions under Trump remain vacant.
"That creates a bit more of a burden, I think, on people like the secretary of state [Rex Tillerson] and the vice president to be available to do high-level traveling," Goldstein said.
Vice presidents since Richard Nixon, who famously held an impromptu "kitchen debate" with Soviet leader Nikita Khruschchev, have had a hand in diplomacy — a trend that Goldstein says accelerated under later vice presidents, including Walter Mondale.
"George H. W. Bush as vice president made 41 trips, or an average of five a year, overseas," said Goldstein.
Pence will make stops in Cartagena and Bogota, Colombia, a country in the process of implementing a controversial peace agreement with the rebel group FARC (Fuerzas Armadas Revolucionarias de Colombia). He also will hear of the nation's efforts to reduce production of coca for cocaine.
In Chile, Pence will face questions over the sudden U.S. withdrawal from the Trans-Pacific Partnership trade pact, Chile's U.S. ambassador Juan Gabriel Valdes told the VOA Spanish service. "With or without the U.S., we will continue working in the Asia Pacific to push for an agreement that results in clear rules for everyone," Valdes said.
He added that his nation hopes the United States does not follow through on the threat to leave the Paris climate agreement because Chile believes that climate change is real.
U.S. trading partner Panama established diplomatic ties with China in June, and Pence's upcoming visit comes against the backdrop of a growing Chinese trade role in the region.
Watch: Pence to Embark on Four-Nation Latin America Tour
Vice presidential roles
Vice presidents do not determine U.S. policy, and none, "including Mike Pence, is going to be taking ownership of, say, foreign affairs, diplomatic relations," said Christopher Devine, a political scientist at the University of Dayton.
"He's contributing to it," he added, "or at least he should be if he's playing the modern role, and what he's doing is helping the president to carry out his policy."
Vice presidents have been key intermediaries and trusted presidential advisers. Analysts say that although Pence's diplomatic role is conventional so far, he works for a president who has promised to do things differently.
Samuel George, an analyst with the German-based Bertelsmann Foundation, said Pence's visit could help strengthen the U.S. presence in Latin America, but the analyst worries about mixed messages.
"I don't know what Trump could tweet," he said. "That's the fear."
VOA's Latin American Service contributed to this report.