MANILA, June 26 (Reuters) - Shanghai rebar steel futures fell to their lowest in nearly four weeks on Tuesday, with risk appetite weakened by escalating trade tensions between the United States and its trading partners.

Conflicting signals from the Trump administration over proposed restrictions on foreign investment in U.S. technology companies, along with news that recently imposed import tariffs are starting to disrupt supply chains, sent global stock markets tumbling on Monday.

U.S. Treasury Secretary Steven Mnuchin has said forthcoming investment restrictions from the department will not be specific to China, but would apply “to all countries that are trying to steal our technology”.

“The abundance of mixed and no less confusing signals are causing massive consternation across all asset classes,” said Stephen Innes, head of Asia Pacific trading at brokerage OANDA.

The most actively traded October rebar on the Shanghai Futures Exchange closed down 1.8 percent at 3,675 yuan ($561) a tonne. The construction steel product earlier touched 3,663 yuan, its weakest since May 31.

A spike in stockpiles of Chinese steel products after 14 straight weeks of decline, also weighed on sentiment, suggesting softer steel demand in the world’s top consumer.

Among steelmaking raw materials, coke futures on the Dalian Commodity Exchange were the hardest hit, falling 3.9 percent to settle at 2,025.50 yuan per tonne, just off the session’s low of 2,020 yuan, the weakest since June 7.

Top iron ore miners Vale and BHP said they and Samarco have signed a deal with Brazilian authorities that settles a 20 billion reais ($5.30 billion)lawsuit related to a 2015 dam burst that killed 19 people.

BHP said the agreement sets a two-year timeline to reach a settlement over a separate 155 billion reais lawsuit, which will remain suspended while the parties continue to negotiate. It did not give a timeline on when operations may resume.