SINGAPORE, Dec 22 (Reuters) - Asia"s cash premiums for 0.5% very low-sulphur fuel oil (VLSFO) rose on Wednesday, buoyed by steady demand and tighter supplies. Cash premiums for Asia"s 0.5% VLSFO climbed to $19.10 a tonne to Singapore quotes, up from $16.15 per tonne on Tuesday. The front-month VLSFO crack dipped 2 cents to $14.99 per barrel against Dubai crude during Asian trading hours. Meanwhile, the 380-cst HSFO barge crack for January traded at a discount of $11.09 a barrel to Brent on Wednesday, compared with minus $10.97 a barrel on Tuesday. Cash premiums for 380-cst high sulphur fuel oil (HSFO) fell to $1.29 cents per tonne to Singapore quotes, down from $1.35 per tonne in the previous session. INVENTORIES - Fujairah Oil Industry Zone (FOIZ) inventories for heavy distillates and residues rose 1.2% or 106,000 barrels (about 15,800 tonnes), from the previous week to 8.9 million barrels (1.3 million tonnes), data via S&P Global Platts showed. - Compared with year-ago levels, the weekly fuel oil inventories at FOIZ were about 20% lower. - Fuel oil stocks at FOIZ have averaged 10.3 million barrels so far this year, compared with a weekly average of 12.9 million barrels in 2020, Reuters calculations showed. WINDOW TRADES - One 380-cst HSFO trade, no VLSFO deals OTHER NEWS - Indonesian state-energy company PT Pertamina has issued a tender seeking up to 1.2 million barrels of high speed diesel (HSD) for January delivery. The company said ensuring fuel supply was its "top priority" as its workers" union is due to hold a national strike from Dec. 29 to Jan. 7 after failing to reach a deal with management over labour terms. - South Korean refiner SK Energy plans to shut its 60,000 barrel-per-day (bpd) crude unit in Ulsan between March and April for a month of routine maintenance, an official of SK Innovation Co Ltd told Reuters on Tuesday. read more ASSESSMENTS FUEL OIL CASH ($/T) ASIA CLOSE Change % Change Prev Close RIC Cargo - 180cst 417.09 13.22 3.27 403.87 Diff - 180cst -1.13 0.15 -11.72 -1.28 Cargo - 380cst 410.24 12.49 3.14 397.75 Diff - 380cst 1.29 -0.06 -4.44 1.35 Bunker (Ex-wharf)- 380cst 413.00 12.00 2.99 401.00 Bunker (Ex-wharf) Premium 2.76 -0.49 -15.08 3.25 For a list of derivatives prices, including margins, please double click the RICs below. Brent M1 180cst M1 180cst M1/M2 180cst M2 Visco M1 Visco M2 380cst M1 380cst M1/M2 380cst M2 Cracks 180-Dubai M1 Cracks 180-Dubai M2 East-West M1 East-West M2 Barges M1 Barges M1/M2 Barges M2 Crack Barges-Brent M1 Crack Barges-Brent M2 Reporting by Koustav Samanta; Editing by Krishna Chandra Eluri