The airline will reduce its Manchester-Singapore route from a daily to a five times a week B777-200 service with effect from November 5.
It means there will no longer be a Tuesday or Thursday flight out of Singapore or a Wednesday or Friday service back from Manchester.
SIA was unavailable for comment but the cuts are believed to be related to the economic downturn and the need to better optimise the extra seats which the carrier will soon be providing out of Heathrow.
It means that Mancunians wishing to fly to or from Singapore on days when there is no non-stop service will be offered connections through Heathrow with alliance partner Bmi.
The extra seats from Heathrow will be offered from September 20. They are being made available through the use of the A380 superjumbo every day on flight SQ321 departing London at 2205 and on inbound daylight flight SQ318 departing Singapore at 1245. Until then the A380 will operate these services up to four times a week.
Existing A380 flights SQ317 at 1155 from London and SQ322 at 2330 from Singapore remain unchanged.
SIA is one of the most important Asian carriers flying out of the UK. Besides serving Singapore, its flights provide dozens of onward connections both within Asia and on to Australasia.
For more information go to singaporeair.com.
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Alex McWhirter