The northwest Shaanxi province recently urged local departments, as requested by China's state planner and other authorities, to verify local steelmakers' crude steel output in 2020 and explain those whose production exceeded designated capacity or didn't meet it.
Another major steelmaking city Handan in the Hebei province recently issued a notice, asking mills to implement production-control measures in the second quarter.
The measures have sparked concerns of more curbs in the ferrous sector, lifting prices as demand is still strong during the peak season.
The most-active construction rebar on the Shanghai Futures Exchange, for October delivery, rose as much as 4.3% to 5,475 yuan ($843.63) a tonne. It closed up 2.3% at 5,371 yuan.
Hot-rolled coils, used in cars and home appliances, ended up 3.2% at 5,737 yuan per tonne, after rising as high as 5,795 yuan earlier in the session.