Northwest China's Qinghai province has announced that its minimum wage will increase by 28.8 percent on average beginning in September, becoming the 27th province in the country to make the move this year.

The province will raise its minimum monthly wage from 580 yuan ($85) to 770 yuan. The minimum hourly wage will be increased from 6.3 yuan to 8.3 yuan.

Since the eastern province of Jiangsu raised its minimum wage this February, 27 provinces, autonomous regions and municipalities have followed suit.

So far only the Guangxi Zhuang autonomous region, Guizhou and Gansu provinces and Chongqing municipality have yet to increase their minimum wage standards, but they have already made plans to do so, the Beijing News reported on Wednesday.

Currently, the minimum monthly wage standard in Shanghai, which was reset in April to 1,120 yuan, is the highest in China.

Beijing has the highest minimum hourly wage of 11 yuan.

The southernmost island province of Hainan made the highest increase of 37 percent, from 480 yuan to 830 yuan.

Different regions within each province have different minimum wages. According to a regulation by the Ministry of Human Resources and Social Security, provincial governments should adjust their local minimum wage standards at least every two years. However, the ministry permitted a temporary suspension of wage increases in November 2008 due to the global financial crisis.