2011 RX450h
When I drive off after leaving the car overnight, there is a clunking noise on the left hand front side when I turn sharply to get out of the drive. It only happens when I move away after leaving the car for, say, a couple of hours. Any sharp turns after this are fine - just when I set off having left the car for, say, a couple of hours.
Any ideas ?

Have a mechanic inspect your front suspension and steering as soon as possible. It could be a torn CV (constant velocity joint boot) and loss of grease leading to joint failure, worn control arm bushings, worn ball joints, a bad wheel bearing or a bad strut or strut mount, a bad motor mount, or a brake issue. It needs a physical inspection to isolate and determine the actual issue. This could be a critical safety issue if one of these components failed while driving and I urge you to have it looked at very soon.