CARACAS (Venezuela) -- A group of U.S.-backed opposition members attacked the leader of Venezuela's U.S.-backed opposition Saturday, according to his parallel government.

The opposition statement includes a photo showing Juan Guaido being held back while people surround him and someone ripping his shirt off. Parallel government claimed that the group was affiliated with the United Socialist Party of Venezuela (PSUV) and "hit and insulted Guaido". Guaido is currently on a tour of South America, trying to unify and organize his party in advance of a planned primary election.

Guaido described Saturday's attack in an Instagram video as an "ambush" on a San Carlos plant nursery. It is located about 168 miles (270 km) southwest of Caracas. He said that he will continue to be "on street" despite the attack.

He said that those who attacked today, including the leaders or members of the regime's political party, should take responsibility for the incident.

PSUV leaders, who are known for making statements via social media or on state television, didn't immediately respond.

Guaido's supporters were met last week by a torrent of flying plastic chairs, and fisticuffs by allies of President Nicolas Maduro at Maracaibo, west.

Guaido is recognized by the United States and other countries as Venezuela's interim President. After accusing Maduro of manipulating his 2018 reelection as president, they withdrew their recognition of Maduro.

Guaido at the time drew huge crowds of supporters into the streets. But much of that momentum has evaporated. His popularity has fallen from 60% to less than 15% three years ago, to below 15% in February.

Brian Nichols, U.S. assistant Secretary of State for Western Hemisphere Affairs, condemned Saturday's "unprovoked attack on Guaido."

He stated that "this egregious attack threatened lives; the attackers should be held accountable."