Can I use 1st class Royal Mail Stamp for send my letter back

[bowybowi]

I want to fanmail to actor in UK, and ask for autograph.
Can I use 1st class Royal Mail stamp (http://www.ebay.co.uk/itm/NEW-Royal-Mai ... TtO3r7PS-g) for send my letter back to outside UK?
Necessary or not to buy royal mail international stamps (http://shop.royalmail.com/stamp-sheets/ ... ernational)?

I read all threads about this but I quite understand.

Thank you very much

[kimmylee]

You can use any and all UK stamps to return your request, as long as the total value meets or exceeds the postage cost.

So, yes you can use 1st Class stamps, and no they don't have to be international.

In fact, I always recommend using 1st Class stamps