Colombia’s leftwing government has announced that it will not approve any new oil and gas exploration projects as it seeks to shift away from fossil fuels and toward a new sustainable economy.

Irene Vélez, the minister for mines told world leaders at the World Economic Forum in Davos that the time had come for the Andean nation to move away from its reliance on oil and gas and begin a new, greener chapter in the country’s history.

“We have decided not to award new oil and gas exploration contracts, and while that has been very controversial, it’s a clear sign of our commitment in the fight against climate change,” Vélez said during a panel in Davos on Thursday. “This decision is absolutely urgent and needs immediate action.”

Colombia’s president, Gustavo Petro, made ending the country’s long history of economic reliance on oil a key part of his campaign before becoming the country’s first leftist leader in August last year.

But a fractured congress, increasingly bleak economic outlook and a series of policy U-turns from the government have put Petro’s ambitious environmentally friendly pledge in doubt.

The country’s finance minister, José Ocampo, has stepped in on several occasions to contradict government ministers and reassure financial markets after their comments sent the value of the Colombian peso tumbling.

Ocampo has repeatedly told reporters that the country remains open to new oil and gas projects as it relies heavily on the sector’s revenue.

But Petro backed Vélez’s announcement this week, saying that alternative economies would make up the loss from oil, which accounts for around half of all of Colombia’s total export revenue.

“We are convinced that strong investment in tourism, given the beauty of the country, and the capacity and potential that the country has to generate clean energy, could, in the short term, perfectly fill the void left by fossil fuels,” Petro told reporters in Davos.

Vélez’s doubling down on the policy has been met with criticism from economic analysts who say that halting oil exploration will not affect the global demand for fossil fuels while hurting Colombia’s economy.

Colombia should transition toward clean energy but without “killing its golden-egg-laying goose”, Julio César Vera, former president of the Colombian Association of Petroleum Engineers, told Colombian media.

The policy has also been criticised by environmental experts who say the move does not address the country’s key environmental issues, such as cattle-ranching and unsustainable agriculture which are driving deforestation in the Amazon rainforest, nor will it have any significant effect on the global climate crisis.

“Colombia must not sacrifice its economic growth to make itself the champion of energy transition in Latin America,” said Manuel Rodríguez, who in 1991 became the country’s first environment minister.

“This is a childish and populist idea based on a false narrative because according to the studies, we will lose several points of GDP while making next to no effect on the global consumption of fossil fuels. Another oil-producing country will simply make up for Colombia’s shortfall.”