Those crimped on clamps (Oetiker) are one-hit-wonders so any method that gets them off is fine - twist of with screwdriver, cut them with snips or wire cutters, dremel etc.
My answer is gently , because if that is the plastic "through baulkhead " petrol pipe junction, it will be brittle .
Like itchy says , side cutters , it avoid twisting
My best tool for that job is an electric 1/2" finger file applied to the flat area. (Only takes seconds ) Use water to eliminate heat damage though. Not ideally suitable for petrol pipes for obvious reasons. I recently had to use that method to remove the clips when I upgraded the fuel pump and filter pipes under the van. Wasn't very happy about the sparks though :cry
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88 High top 2.1 WBX