What is a good additive-free brand of cigarettes sold in the UK?

I live in America and my brand of choice is Winstons, due to 1. they are additive free and 2. they taste better than any other additive-free brands I've tried (like American Spirit). I'm going to be staying in the U.K. for about a month later in the summer and I recently found out they don't sell Winstons. What would be a good British equivalent brand? I'll be staying in London if that affects the answer to this question at all.