Use of KrisFlyer miles to upgrade on United Airlines?

[jse]

I have received conflicting advice regarding using KrisFlyer mile to upgrade on a United Airline flight.

Over the phone I was told that you absolutely cannot use miles earned on one Star Alliance carrier to upgrade a fare on another carrier.... AND

Over the counter I was told that you can use KrisFlyer miles to upgrade a United fare as long as you book your United flight through Singapore Air.

Has anyone out there had any experience with this issue?

Thanks

James

My apologies if this topic has been previously discussed.

[clifford]

Can't be done, I'm afraid.

Neither can you use Mileage Plus miles to upgrade on SQ.

[Kiwi Flyer]

Only SQ miles or DL miles can be used to upgrade on SQ. Next year there will be the introduction of allowing any *A miles to upgrade on any *A carrier (will be phased launch though only some carriers initially).