Wineworks have for about a fiver a screw in adapter for the needle valve which supposedly fits 3/4 BSP washing machine taps, in fact it has a 20mm thread which is close and can be forced on 3/4 BSP but is not ideal and I wouldn't do it, the last thing you want is for leaks to develop when your half way into a run.
A better option is to solder a short piece of 13mm copper pipe into the little adapter supplied with the needle valve, shove a hose pipe on the end and jubilee clip it.
If you cannot easily get a hose pipe to it then a self cutting tap adapter, with 3/4 BSP thread, set into the nearest cold pipe, available at B&Q is, the way to go.
http://www.ultimatehandyman.co.uk/how_t ... ng_tap.htmYou can then use Hozelok fittings on the hose to connect straight to it, better still use a compression fitting on the short piece of copper and go straight into the tap without any hose pipe.
http://www.amazon.co.uk/15mm-Compressio ... B005HB32JI