Is black clothing compulsory?

I just wondered whether it is now compulsory for cyclists to wear black
clothing? I ask because I nearly wrote a cyclist off early yesterday
morning. He was cycling slowly up a hill in the middle of the road. Dark
clothes and dark bike = all I could see was the rear light.

I thought what I was looking at was a motorcycle 50m ahead, whereas what
I was actually seeing was a cyclist just 10m ahead.

No doubt, I'd have been held to blame for the accident, if I hadn't
stopped just in time. Nevertheless, I was quite safe in my car, and the
cyclist is the one who'd have ended up in hospital.

Bear in mind that there are lots of crap car drivers around, like me,
and give them all the help you can not to injure you. It seems a really
good idea to wear light coloured clothes with reflective panels and have
a similar colour scheme for the bike.