Daniel Marx, a former finance secretary in Argentina and debt negotiator, said it had become untenable for Mr. Guzmán to continue in his post amid strong opposition within the government. The big question now is who will replace him.
“It seems important to me to see how the void is filled,” Mr. Marx said. “Not only the person but the economic policy direction to get out from all the skepticism and the problems that have been dragging on for quite some time.”
As of Sunday morning, there was no news on a successor and President Fernández had not yet publicly addressed the departure, suggesting that the government had been caught off guard.
Some investors were concerned about how the departure would affect the country’s ability to meet its obligations with the I.M.F., which include targets for inflation, reserve levels and the fiscal balance — all already under pressure.
“This is not good and confirms that there is a political problem,” said Maria Castiglioni, an economist at CT Asesores Económicos, adding that it raised questions about whether the government would be able to take the necessary measures to deal with the crisis.
Horacio Larghi, economist and director of the consulting firm Invenomica, said what mattered most was whether the new economy minister had license to act.
“As for who replaces him, the name doesn’t matter so much,” Mr. Larghi said. “What matters is whether or not the person will have the power to do anything.”