China's budget deficit is likely to expand in 2013 as the government's increased expenditure and tax reform measures will lower the growth rate of its revenue, Jia Kang, head of the Ministry of Finance's Research Institute for Fiscal Science, said at an economic meeting on Sunday.

Jia said that China's budget deficit of GDP will increase to about 2 percent in 2013 from the targeted 1.5 percent in 2012. He did not disclose the volume of this year's budget deficit but said it will be bigger than the targeted 800 billion yuan ($127 billion) in 2012.

The Chinese government has been boosting spending in infrastructure construction to support economic growth as the world economy faces a slowdown.