* U.S. stock futures down 0.4%, Asian shares down
* U.S. tariffs seen hitting U.S. consumers
* Hong Kong protests escalate, hit Hong Kong shares
* Mainland Chinese shares rise
* European shares seen flat
By Hideyuki Sano
TOKYO, Sept 2 (Reuters) - Global stock prices fell on Monday after the United States and China imposed new tariffs on each other's goods, reinforcing investors' worries over slowing global growth, with no clear end in sight for the trade war.
The E-mini futures for U.S. S&P500 fell as much as 1.06% in early trade and last stood down 0.39% while U.S. Treasuries futures prices rose a tad.
Volumes remained thin in Asia ahead of a U.S. public holiday and European shares are expected to open little changed, with pan-European Euro Stoxx 50 futures almost flat in early Monday trade.
MSCI's broadest index of Asia-Pacific shares outside Japan dropped 0.24%, led by 0.5% drop in Hong Kong's Hang Seng after another weekend of violent anti-government protests.
Chinese shares, however, bucked the bearish trend, with the CSI300 index rising 1.1% despite the trade row escalation. Providing some tailwind to mainland markets was a pledge by China's State Council to boost support for the economy.
Caixin/Markit Manufacturing Purchasing Managers' Index (PMI), a private sector survey, on Monday showed factory activity unexpectedly expanded in August, though gains were modest and contrasted with official data that pointed to further contraction.
"It's clear that Beijing is willing to support the economy through fiscal stimulus," said Kenji Hashizume, senior fund manager at Mitsui Sumitomo DS Asset Management in Hong Kong.
"While I do not expect the Sino-U.S. relations to keep deteriorating, it won't be solved easily either," he said.
Washington slapped 15% tariffs on a variety of Chinese goods on Sunday - including footwear, smart watches and flat-panel televisions - while Beijing imposed new duties on U.S. crude, the latest escalation in a bruising trade war.
Several studies suggest the tariffs will cost U.S. households up to $1,000 a year, with the latest round hitting a significant number of U.S. consumer goods.
In retaliation, China started to impose additional tariffs on some of the U.S. goods on a $75 billion target list. Beijing did not specify the value of the goods that face higher tariffs from Sunday.
Although U.S. President Donald Trump has said the two countries will hold talks in September, there are doubts any such talks would lead to a breakthrough.
"So far Trump appears defiant though on the tariff hikes, blaming the Fed and American companies for their difficulties in dealing with the tariffs," said Shane Oliver, chief economist at AMP in Sydney.