Chinese companies are trying to evade a new law that will make it harder to sack employees, prompting a government warning that they may have to pay "a heavy price," state media said Friday.

The Labour Contract Law, to take effect early next year, offers staff with more than 10 years of service at a company the right to sign a new contract that will make it harder to fire them, the China Daily reported.

In an apparent bid to evade the law, major telecom equipment maker Huawei recently ordered 7,000 employees who had been with the company for more than eight years to quit and then reapply, according to the paper.

"We have carried out probes into such cases," an official with the state-controlled All China Federation of Trade Unions told the paper.

The practice is apparently so widespread the government is planning special regulations dealing with companies that seek to evade the new law.

"Violators will have to pay a heavy price," said Chang Kai, an official with the Legal Affairs Office of the State Council, or Cabinet, according to the paper.

A spokeswoman at Shenzhen-based Huawei, in south China, told AFP she did not know the exact reasons why 7,000 people had been told to resign and reapply for their old positions.

"We don't have any official statement on this issue," she told AFP by telephone.

China is notorious for frequent violations of basic labour rights, often made possible as company owners colluding with local officials.