The unexpected action is intended to tamp down a potential bubble in the bond market fueled by investors shunning riskier assets like stocks and real estate.

China's central bank suspended treasury bond purchases on Friday, briefly lifting yields and spurring speculation it is stepping up defence of the yuan currency which has been sliding since the election of Donald Trump as U.

The bank halted its government bond purchases Friday in an attempt to slow a one-way bonds trade that’s put unwanted downward pressure on the yuan, analysts say.

China's central bank is expected to deploy its most aggressive monetary tactics in a decade this year as it tries to stimulate the economy and soften the blow of impending U.S. tariff hikes, but in doing so it risks quickly exhausting its firepower.