How to action MT look-up only for occasional segments

I'd like to perform a look-up with RWS Language Cloud only occasionally. At the moment, MT is triggered when my TM returns nothing and the MT suggestion (from RWS Language Cloud) appears in the Translation Results window. The suggestion in the top window distracts me when I'm busy translating the active segment – it interrupts my train of thought.

Is it possible to perform MT look-up on demand only? I can do it through GT4T with a simple shortcut, but I'd like to do it through the Language Cloud.