What is this wild plant?

Looks like White Bryony (Bryonia dioica) to me, though the flowers do seem rather white - they're usually creamier. White bryony produces berries which start out green ,turn yellow and then orange as they ripen, so you could see what it looks like later to confirm the ID.

Thanks Bamboo, perhaps the photo flatters.

But its very poisonous

And the berries absolutely stink when you crush them!!

eeugh, I've gone off it now :-(

As our only native Curcurbit (melon/pumpkin/squash family) it is still interesting. I wouldn't mind it in a wild area of my garden. I just wouldn't squash the berries...no pun intended! :-)

You don't see this pretty plant about so much in the countryside now (like many other things!) so if you have room, let it row. The berries are very attractive--just don't touch them!