CIO

It was a massive operation, which followed a warning from the CIO that the presidential security team could also be arrested if they tried to block Yoon's arrest again.

"I decided to appear before the CIO, even though it is an illegal investigation, in order to prevent any unsavoury bloodshed," he said.

At one point the security team engaged in a "confrontation with the CIO at the presidential residence", an official with Seoul's Joint Chiefs of Staff told AFP.

"The most likely scenario is that we see both parties sitting down with a clean sheet of paper and redesigning the program," said Alejo Czerwonko, CIO for Emerging Markets Americas at UBS Global Wealth Management.

Gary Dugan, CIO at Dalma Capital, said the move underscores the significant structural challenges facing the US economy, characterized by unsustainable levels of debt and fiscal leniency.