BUZZ-Australian mining stocks eye worst day in over 6 weeks on US tariffs on China

** Australian mining stocks index .AXMM fall 2.2% heading for their biggest fall since Dec. 19, if losses hold

** Subindex hits lowest level since Jan. 13

** Over the weekend, U.S. President Donald Trump imposed tariffs on China, Australia's top trading partner and a major consumer of iron ore used for manufacturing steel

** Trump's tariffs are likely to weigh on the growth for Australian mining companies due to their exposure to China

** Shares of BHP Group BHP.AX and Rio Tinto RIO.AX fall over 2% each

** Rio shares hit lowest level since Jan. 7

** AXMM up 3.6% this year as of last close, vs a more than 4% increase in the benchmark index ASX 200 .AXJO