Colombia's first leftist president was inaugurated on Sunday, promising to combat inequality and marking a turning point in the country's history, marred by a protracted conflict between the government and guerrillas.

Sen. Gustavo Petro, a former member of Colombia's M-19 guerrilla group, won the June presidential election by defeating conservative parties that offered moderate changes to the market-friendly economy but failed to connect with voters frustrated by rising poverty and violence against human rights leaders and environmental activists in rural areas.

Petro is a member of a growing group of leftist politicians and political outsiders who have been winning elections in Latin America since the pandemic outbreak, which harmed incumbents struggling with its economic repercussions.

The election of the ex-rebel was also unprecedented in Colombia, where voters have typically been hesitant to support leftist politicians who are frequently accused of being soft on crime or connected with militants.

A 2016 peace agreement between the Colombian government and the Revolutionary Armed Forces of Colombia shifted voters' attention away from violent conflicts in rural areas and toward issues such as poverty and corruption, boosting leftist parties' support in national elections.

62-year-old Petro has pledged to address Colombia's social and economic disparities by increasing anti-poverty spending and rural investment. He has referred to U.S. anti-drug tactics, such as the forced removal of illegal coca fields, as a "huge failure." However, he has stated that he would prefer to cooperate with Washington "as equals," constructing projects to tackle climate change or bringing infrastructure to remote areas where coca leaves are the only viable crop, according to many farmers.

During his presidential campaign, Petro also forged partnerships with environmentalists. He pledged to transform Colombia into a "global powerhouse for life" by stopping deforestation and reducing the country's reliance on fossil fuels.

The incoming president has stated that Colombia will cease issuing new permits for oil exploration and prohibit fracking operations, even though the oil industry accounts for about half of the country's legal exports. He intends to pay for social spending with a $10 billion-per-year tax overhaul that would increase taxes on the wealthy and eliminate tax advantages for corporations.

Petro has also stated that he wants to begin peace talks with the other guerrilla factions now battling over abandoned drug routes, gold mines, and other resources abandoned by the FARC following their peace agreement with the government.

According to a political scientist at Bogota's Rosario University, Yan Basset, he has a reasonably ambitious goal. However, he must establish priorities. The risk Petro confronts is that he pursues too many reforms simultaneously and obtains nothing from Colombia's congress.

Eight heads of state were present at Petro's inauguration, which was held in a vast colonial-era square in front of Colombia's Congress.

For tens of thousands of citizens who were not invited to the main event to participate in the celebrations, stages with live music and large screens were placed in parks throughout the city center of Bogota. This represented a significant change for Colombia since prior presidential inaugurations were more solemn affairs with fewer than a thousand VIP attendees.

"This is the first time that people from the base can attend a presidential inauguration," said Luis Alberto Combe, a Guambiano tribesman. He attended the swearing-in ceremony while wearing a traditional blue poncho. "We are privileged to be here."