Noise from front suspension

Hi all. New member here. Please can someone suggest what the issue is with my Meriva 1.7 cdti Design ? There is a dull clunking noise from the front of the vehicle (every few seconds) when have any lock on the steering on both RH and LH sides. Doesn't make the noise when steering in a straight line - but it's there as soon as you put any lock on. It's quite loud - every few seconds at low speed (haven't tried to go any faster - I just put the car away again. Have googled this but apparently it can be one of several things causing this noise so I'm not wiser and thinking the worst about the cost of repairs. Please could anyone advise if they've had a similar issue, particularly with the Meriva A 2002 - 2007, and the approximate cost of repairs. TIA. Gary