South Korean President Lee Myung-Bak arrived on Tuesday in Riyadh at the start of a two-day visit to the OPEC kingpin which comes as Seoul seeks to diversify its oil sources.
"South Korean President Lee Myung-Bak arrived with his delegation in Riyadh today in an official visit to the kingdom," Saudi state news agency SPA reported.
Lee's office had said that he is expected to meet with Saudi King Abdullah for talks on strengthening cooperation in energy, construction and other areas.
The president's trip to the Middle East will help South Korea "secure a stable supply of energy resources", his office said.
The United States wants its close ally South Korea to reduce purchases of Iranian crude in line with a US-led drive to sanction Tehran for its suspected nuclear weapons programme.
South Korea, the world's fifth largest oil importer, currently accounts for around 10 percent of Iran's oil exports. It has yet to cut the import of Iranian oil due to fears of economic damage.
In mid-November, Saudi Arabia announced that it had signed an agreement with South Korea on developing nuclear power generation to help meet rising demand in the kingdom, Iran's regional arch foe.
Lee will also visit the kingdom's gas-rich neighbour Qatar on Thursday and make a stop in the United Arab Emirates on his way home.