I am working at lists like these, filling them with numbers about UK's trade with it's biggest partners. The problem is, I can't find such data for the years before 2010. I know that the institution (Office for National Statistics - ONS) changed it's website in 2009 or so, and maybe it has to do something with that, but I can't find the data on the older site also.
The OECD has nearly the exact data you are looking for. I haven't figured out how to get it into a raw data dump. I am pretty confident that this problem has more to do with me than it does with the data available.
The WTO holds similar quality information. I think somewhere a UK govt body is publishing this. Not sure where exactly though.
The UN has everything you need but you need to sign up.
See this question for other trade related sources: