Qatar signed a 20-year agreement with South Korea on Thursday for the sale of two million tonnes of liquefied natural gas a year, during a visit by President Lee Myung-Bak to the energy-rich Gulf state. Qatar\'s Ras Laffan is to deliver the annual shipments starting in 2013, in addition to incremental medium-term volumes from 2012 to 2016, the company ResGas said in a statement. The agreement was signed by RasGas subsidiary Ras Laffan Liquefied Natural Gas Co Limited (3), or RL3, and Korea\'s KOGAS, on the day Lee arrived in Qatar, his second stop in a Gulf tour following a visit to Saudi Arabia. The two countries already have two long-term LNG purchase agreements, the first dating back to 1995 under which Qatar delivers 4.9 million tonnes annually (Mta), and the second signed in 2007 for 2.1 Mta. Qatar is the top natural gas exporter to South Korea, accounting for 23.7 percent of the country\'s entire natural gas imports, according to a presidential statement released ahead of Lee\'s visit. The small emirate, which holds the world\'s third-largest gas reserves, last year celebrated raising its production capacity for LNG to 77 Mta, boosting its position as the world\'s largest producer. Lee arrived in Doha for talks on oil supplies and construction projects for the 2022 World Cup finals to be held in Qatar, according to an interview with a local daily. The scheduled two-day visit came after the South Korean president, expected to visit the United Arab Emirates after Qatar, secured Saudi pledges to ensure a stable supply of oil to the east Asian nation. Lee said in comments published on Qatari daily Al-Sharq\'s website on Thursday that his discussions with the emir, Sheikh Hamad bin Khalifa Al-Thani, would focus on \"energy, climate change and green growth.\" According to an Arabic translation of his interview, Lee said he also \"anticipates cooperation between the two countries\" in the development of infrastructure ahead of the 2022 games. The South Korean president hailed Qatar\'s diplomatic efforts in the wake of the Arab Spring revolutions, saying the Gulf state had played a \"prominent role in resolving conflicts and establishing peace and stability in the Middle East.\" In South Korea, oil refiner S-Oil said Thursday it had signed a 20-year supply deal with Saudi state oil giant Saudi Aramco. Saudi Aramco will provide about 230 million barrels of crude oil each year, about 30 percent of the country\'s total annual consumption, said S-Oil, the nation\'s third-largest oil refiner. S-Oil does not import from Iran. But it said the deal offers assurances that its needs will not be disrupted by \"serious volatility in the market\" due to sanctions on Iranian crude for its suspected nuclear weapons programme. Lee met Saudi King Abdullah on Wednesday in Riyadh, where they agreed to \"bolster bilateral relations in a variety of sectors,\" according to a statement by the Saudi news agency SPA. Their meeting came after Lee held talks with Saudi Oil Minister Ali al-Naimi and the Saudi Aramco head, Khalid al-Faleh. \"Regarding oil supply-demand, we will meet any request and additional demand from South Korea,\" Korean presidential press secretary Choe Geum-nak quoted Naimi as saying. The kingdom also agreed to strengthen defence cooperation with South Korea. Washington wants close ally Seoul 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, accounts for around 10 percent of Iran\'s oil exports but has yet to cut Iranian crude imports due to fears of economic damage. In 2011, top world oil exporter Saudi Arabia sold 270 million barrels of oil to South Korea, accounting for 31.4 percent of Seoul\'s entire oil imports.