as small as you can buy - 1A @ 240v is still 240W, so normal incandescent bulbs will take a quarter of that, low energy ones a twentieth. The smallest plug fuses readily available are probably 3A. To be fair, though, the fuse protects the cable, so as long as the cable will carry 3A without heating effects, 3A fuses will be fine. 1A if they can be found, though.
If an doubt of any misuse (or the general public) stick the whole lot on a plug-in RCD adapter, too.
no subject
If an doubt of any misuse (or the general public) stick the whole lot on a plug-in RCD adapter, too.