Friday will see U.S.

President Donald Trump reveal his revisions to a tariff list targeting $50 billion worth of Chinese goods.

For Beijing it's not so much about what's on it, but that there's rumours of a SECOND list being worked on - targeting a further $100 billion worth of products in case China retaliates - which, it seems, is inevitable. (SOUNDBITE) (Mandarin) CHINA FOREIGN MINISTRY SPOKESMAN, GENG, SHUANG SAYING: "If the United States takes unilateral, protectionist measures, harming China's interests, we will quickly react and take necessary steps to resolutely protect our fair, legitimate rights." Investors are bracing for more trade tit-for-tat with global shares set to end the week in the red on Friday.

Chinese stocks led the losses with the benchmark Shanghai Composite index plunging to a 20-month low.

It's unclear when the tariff's will come into effect - Washington and Beijing have already held several rounds of failed negotiations. (SOUNDBITE) (English) DARREN SINDEN, MARKET ANALYST, PEPPERSTONE, SAYING: "At the moment it is sort of death by a thousand cuts and these things are quite modest and not blanket orientated by any means, but if Mr trump keeps raising the anti then we could see protectionism and trade tariffs become the norm rather than a relative thing of the past and of course the next thing after that might be people turning to their currency and using that as a weapon in trade wars as well as imposing tariffs on imported goods." In Europe it was monetary policy moving the markets.

Shares there were set for their best week in more than three months - after the ECB signalled interest rates would be left at record lows until half way through next year.

That though, dragging down the euro to its worst weekly loss in 19 months.