SINGAPORE, Jan 30 (Reuters) - Asia's very low sulphur fuel oil (VLSFO) market softened at the end of the week, while high sulphur fuel oil (HSFO) extended gains.

Singapore's VLSFO cash differential slipped below $2 a metric ton on Friday, while front-month market structure sank into a contango. Prompt supply is expected to be steady to higher into February, trade sources said.

Meanwhile, HSFO backwardation eased slightly on Friday, though cash premium for the product continued to trek higher, closing above $8 a ton.

Cracks for both grades fell, with February 380-cst HSFO crack FO380BRTCKMc1 closing at a discount near $4.15 a barrel, while VLSFO crack LFO05SGBRTCMc1 slipped to a premium near $3 a barrel, LSEG data showed.

INVENTORY DATA

- ARA fuel oil inventories STK-FO-ARA rose 3.1% to 1.16 million tons in the week to January 26, based on data from Dutch consultancy Insights Global.

OTHER NEWS

- Oil fell on Friday on signs the U.S. may engage in dialogue with Iran over its nuclear programme, reducing concerns of supply disruptions from a U.S. attack, though prices were on track for large monthly gains as tensions have increased. O/R

- The peak maintenance periods for Russian primary oil refining this year are expected this month and in September, based on Reuters calculations using estimates from industry sources.

- U.S. private equity firm Carlyle Group has agreed to an initial deal to buy most of Lukoil's foreign assets, which Russia's second-largest oil company is being forced to sell because of U.S. sanctions.

- The administration of President Donald Trump lifted some sanctions on Venezuela's oil industry on Thursday to make it easier for U.S. companies to sell its crude oil, and said more restrictions on the country would be lifted soon.

WINDOW TRADES O/AS

- 180-cst HSFO: No trade

- 380-cst HSFO: One trade

- 0.5% VLSFO: No trade

ASSESSMENTS

(Reporting by Jeslyn Lerh; Editing by Shailesh Kuber)

((jeslyn.lerh@thomsonreuters.com))