Nationwide law enforcement departments helped 6.22 million workers collect about 20 billion yuan ($3.2 billion) in delayed wages in 2012, Yin Weimin, minister of human resources and social security, said on Friday.

Migrant workers are most vulnerable to wage delays.

Twelve ministry-level departments, including Yin's ministry, the Ministry of Public Security and the Ministry of Housing and Urban-Rural Development, held a teleconference on Friday during which they asked grassroots authorities to improve handling of labor disputes to ensure the country's 250 million migrants receive the wages that they are due before Spring Festival, which falls on Feb 10 this year.