* China’s 2018 GDP growth at lowest since 1990
* South Korea’s economic growth slows to a 6-year low
* IMF downgrades 2019 global growth forecast
* OPEC-led supply cuts support crude prices (Adds South Korea GDP data, quotes, updates prices)
Oil prices fell on Tuesday as signs of a spreading global economic slowdown stoked concerns over future fuel demand.
International Brent crude oil futures LCOc1 were at $62.26 per barrel at 0410 GMT, down 48 cents, or 0.8 percent, from their previous close.