SEOUL – South Korean President Yoon Suk-yeol’s approval rating has fallen to its lowest level in about six months, dragged down by his response to leaked documents that purportedly showed the United States spied on its ally.

Support for Mr Yoon dropped four percentage points to 27 per cent in a weekly tracking poll released on Friday by Gallup Korea. Disapproval of the President’s performance increased by four percentage points to 65 per cent.

In the poll, diplomacy was the factor most mentioned in both positive and negative assessments of Mr Yoon’s performance, the research company said. The issue took on greater relevance after documents in US media reports indicated that the US spied on Mr Yoon’s office, while the government in Seoul has tried publicly to downplay friction with its American ally.

A New York Times report claimed the US has been eavesdropping on allies, including South Korea, with regard to plans to support Ukraine with weapons. The South Korean government has a policy of not providing lethal weapons to Ukraine, but the documents have led to interpretations suggesting Seoul is indirectly supporting Ukraine through the US.

Mr Kim Tae-hyo, a top South Korean security official, told reporters this week that Seoul and the US agreed that a significant portion of the documents relating to the two allies had been fabricated. He said the countries’ defence ministers spoke by phone and their views were aligned.

Mr Yoon is set to go to Washington for a state visit in less than two weeks, where US President Joe Biden is likely to seek the help of the South Korean leader in imposing sweeping curbs on the sale of advanced chips equipment to China.

The policy is aimed at preventing China’s progression in a range of cutting-edge technologies that could threaten America’s status as the world’s pre-eminent power.

The move by its main security ally, the US, has put South Korea in a bind. China is the country’s biggest trading partner, and South Korean tech giants Samsung Electronics and SK Hynix both depend on China as a key market and a manufacturing site for their memory chips.

Mr Yoon has been an advocate of Washington’s Asia strategy, including Mr Biden’s initiative to restructure global supply chains to reduce dependence on China.

In pursuit of this goal, he has proposed a resolution for a longstanding dispute over compensation for Japan’s use of Korean forced labour during its 1910-45 occupation of the peninsula. However, the proposal, which entails South Korean firms paying into a compensation fund for conscripted Korean workers, has been met with disapproval by a majority of the South Korea public, polling has shown.

South Korea’s political opposition has been critical of Mr Yoon’s administration over the deal with Japan and the leaked documents. Democratic Party head Lee Jae-myung and floor leader Park Hong-geun have urged the Yoon administration to request information from the US about the leaks and have called for an apology to prevent any recurrence in the future. BLOOMBERG