How do I remove the pop-up plug from basin in Bailey Vigo?

[brissle]

Advice please,
We have come away in our 2020 Bailey Unicorn Vigo caravan and have found that the pop-up plug in the bathroom basin will not seal. So water runs away as soon as we turn on the tap.
Research tells me that I can replace the washer, but at the moment I cannot discover how to remove the plug.
Various websites tell me to turn the plug either clockwise or anti-clockwise, but neither will let me turn the chromed plug, by hand even when gripped with a cloth.
Before I put an adjustable spanner on it, can someone please tell me definitively, which way to turn the plug?
Many thanks

 

[Mr Plodd]

ANTI-clockwise

 

[brissle]

Thank you. That worked.
Now another question, please.
I had imagined that the whole mechanism would come out with the chrome cap, but the cap has just unscrewed from the pop-up stem.
Should there be a seal round the underside of the chrome cap - an O-ring or something?
At the moment there's nothing there. Photo attached.
Thanks for your help.

 

[birdman101]

They usually have a seal around the outer on domestic ones. Have a look at Screwfix

 

[toad a caravan]

Try Toolstation also,,check in their plumbing section

 

[brissle]

That seems absolutely logical - thank you again.
I'll try Screwfix if there's one nearby to where we are staying (Cullompton, Somerset) or maybe a local caravan dealer. Time to research.
Thanks again from sunny Somerset.