South Korea's consumer sentiment rose to a four-year high in June, driven by eased political uncertainties and optimism over the government's supplementary budget and other supportive measures, the central bank said on Tuesday.

The composite consumer sentiment index (CCSI) stood at 108.7 this month, up 6.9 points from May, according to a survey conducted by the Bank of Korea (BOK), reports Yonhap news agency.

It marked the highest level since June 2021, when the index reached 111.1.

Consumer sentiment had plunged to below 90 in December following former President Yoon Suk Yeol's imposition of martial law and remained in the 90-range before climbing above 100 in May.

A reading above 100 indicates that optimists outnumber pessimists, while a figure below 100 means the opposite.

President Lee Jae Myung has pledged full-scale efforts to boost economic growth and support people's livelihoods through a supplementary budget and other policy measures.

Last week, the government announced a second supplementary budget worth over 20 trillion won (US$14.47 billion), following a 13.8 trillion-won package approved by the National Assembly in May.

"With the supplementary budget expected to pass the National Assembly soon, the current trend is likely to continue for the time being," BOK official Lee Hye-young said during a press briefing.

"But uncertainties remain over the United States' tariff policy and the ongoing Middle East conflict. We will need to closely monitor how these external factors may affect consumer sentiment going forward," the official added.

Meanwhile, South Korean stocks jumped over 2 per cent higher late on Tuesday morning over eased tensions in the Middle East after US President Donald Trump announced that Israel and Iran have agreed on a ceasefire to end their conflict.

The benchmark Korea Composite Stock Price Index (KOSPI) soared 68.65 points, or 2.28 percent, to 3,083.12 as of 11:20 a.m.

Trump made the announcement after Iran fired short- and medium-range ballistic missiles at Al Udeid Air Base in Qatar -- the largest U.S. military installation in the Middle East -- in response to America's attack on three key nuclear sites in Iran over the weekend.

Trump said that without the ceasefire, the war could have gone on for years and destroyed the entire region.