What's the nearest UK equivient to "A1 Steak Sauce"?

A common theme on threads is that when discussing condiments it seems to be near-universally agreed by American posters that A1 Steak Sauce is delicious. Having never tasted it I obviously have no opinion on the matter. But maybe it’s known by a different name here, or some brand of sauce tastes remarkably like it. So, any Dopers who have spent time on both sides of the Atlantic, what’s the most similar thing out there on UK shelves?

A1 is like a tangier HP sauce. I just tasted both, and there is a distinct similarity. But the A1 has more tang to it. More vinegar, maybe?

It’s a bit like Worcestershire sauce, too.

I’ll take HP over A1 any day of the week, but there are definite similarities.

edit: I’d be surprised if A1 has more vinegar than HP, btw.

HP sauce is the equivalent at least in market share.

Obligatory Wiki link

For comparison:

If you gave me those two lists of ingredients without the product, I would place them wrong. Marmalade and chutney seem so much more British, while tomato and tamarind seem more like American tastes (or Mexican).