SINGAPORE - Sales of marine fuels in Singapore, Asia's biggest ship fuelling port, fell 9.5 percent in November from a year earlier to a 17-month low of 3.906 million tonnes, data from the Maritime and Port Authority of Singapore (MPA) showed on Thursday.

The November volume was 5.3 percent lower than October when 4.125 million tonnes were sold.

The number of ships that called in November at Singapore for refuelling, also called bunkering, fell 2.5 percent from October to a three-month low of 3,255 ships. Compared to year-ago levels, however, bunkering calls in Singapore in November were up 1.6 percent.

The lower bunkering traffic in November was attributed to the spike in marine fuel costs during the month as tightening Singapore supplies pushed ex-wharf bunker fuel premiums to more than $20 per tonne, two trade sources said.

Premiums for 380-centistoke marine fuel oil loading ex-wharf averaged about $17 per tonne to Singapore in November compared to an average of about $8 per tonne in October, Reuters data showed.

Reflecting the lower bunkering activity at Singapore, vessels loaded an average of 1,200 tonnes each of bunkers in November, also a 17-month low, and down from 1,235 tonnes in October and lower than the record 1,347 tonnes loaded a year earlier, Reuters calculations showed.

The average volume loaded by each ship so far in 2018 has totalled 1,264 tonnes.

The lower November sales volumes means Singapore is unlikely to set a new record for annual bunker fuels sales, breaking a three-year streak.

Singapore marine fuel sales in the first 11 months of 2018 totalled 45.491 million tonnes, down 2 percent from the record 46.344 million tonnes sold in the same period last year, MPA data showed.

In order to match its record 50.6 million tonnes of marine fuel sales set in 2017, Singapore would have to report sales volumes of 5.145 million tonnes in December.

Singapore's monthly sales volumes have averaged 4.136 million tonnes since the start of the year.

Jan 4606 3.2% 29 -11.4% 3370 0.9% 980 9.7% 115 -2.3% Jan 12642 6.0% 3472 Feb 4136 7.5% 32 8.6% 2916 -0.1% 959 34.8% 128 24.8% Feb 11130 4.4% 3094 Mar 4168 -4.0% 27 -12.5% 3103 -5.1% 826 -1.8% 119 4.3% Mar 12546 1.9% 3414 Apr 4233 -0.5% 23 -0.2% 3023 -5.1% 926 5.7% 126 23.7% Apr 12133 -1.0% 3329 May 4283 2.5% 31 32.6% 2948 -5.6% 1010 17.9% 110 7.0% May 12225 -3.4% 3237 Jun 3922 2.2% 29 226.9% 2796 0.4% 853 -3.3% 107 8.1% Jun 11192 -8.8% 3130 Jul 4036 -8.1% 27 -7.3% 2918 -11.7% 841 -0.5% 100 -3.9% Jul 11605 -1.7% 3297 Aug 3963 -9.2% 20 6.5% 2817 -12.9% 877 -1.8% 126 14.7% Aug 11389 -4.4% 3128 Sep 4112 -5.3% 30 38.4% 2981 -7.3% 843 -4.1% 133 21.3% Sep 11367 -2.2% 3310 Oct 4125 3.0% 24 -10.5% 2992 -2.4% 835 19.8% 143 47.2% Oct 11629 -7.3% 3340 Nov 3906 -9.5% 29 11.3% 2786 -11.5% 824 -8.4% 141 30.6% Nov 11187 -9.3% 3255 Total 45491 302 32650 9774 1348 129045 36006

(Reporting by Roslan Khasawneh; Editing by Christian Schmollinger) ((roslan.khasawneh@thomsonreuters.com; Reuters Messaging: roslan.khasawneh.thomsonreuters.com@reuters.net; +65 6870 3121))