Chinese companies Thursday denied allegations by a Zimbabwe trade union that said Chinese construction firms had violated labor laws there by underpaying and abusing local staff.

Ge Yizhong, deputy general manager of Zim Nantong Construction, which is currently operating in Zimbabwe, told the Global Times that local workers his company had hired were satisfied with their working conditions, including salaries.

"There is no ill-treatment of workers at my company. We have provided protective clothing to local workers and pay them according to the regulations set out by the local trade union," he said. "We have adjusted working hours to meet workers' demands. We have raised their pay twice since last year to counter the devaluation of the local currency."

Commenting on the allegations against Chinese companies, Ge said competition may prompt local unions to make such allegations, as more Chinese companies are doing business in Africa.

His defense comes after the Zimbabwe Construction and Allied Trades Workers' Union accused Chinese construction firms operating in Zimbabwe of underpaying workers, forcing them to work overtime without pay and not providing them with protective clothing and pension contributions, Newsday, a Zimbabwe-based newspaper, reported Wednesday.

"We would like to warn the Chinese contractors who are operating in Zimbabwe that if they do not follow the laid-down laws, the union is going to take strong action against them," the union's secretary-general, Muchapiwa Mazarura, was quoted by the paper as saying.

The construction union also said that the deals that the government entered into with the Chinese should not be compensated by Zimbabwe "donating human resources," adding that inhuman treatment of workers should come to an end, the report said.

The Affirmative Action Group, a Zimbabwean lobby group, recently wrote to the Harare Municipality asking local authorities to stop licensing foreigners, especially the Chinese, as they were not bringing any real business to the country, according to the report.

The trade volume between China and Africa surged from $1 billion in the early 1990s to a historic high of $106.8 billion in 2008 is expected to top the 2008 figure by end of the year, according to China's Ministry of Commerce.

Direct investment from China to Africa grew from $80 million in 2003 to $1.36 billion in 2009.

With growing trade between China and African countries and a surge in Chinese businessmen investing in the continent, disputes between Chinese and local Africans are on the rise.

In September, there were two cases involving gunmen in Zimbabwe robbing the sites of Chinese construction groups stationed in the country, resulting in property losses and injuries to Chinese nationals, according to the Chinese Ministry of Foreign Affairs.

Last month, Zambian police arrested two Chinese nationals who shot at 11 miners and one onlooker at the Chinese Collum Coal Mine in Zambia, the local Lusaka Times reported.

Guo Wenchang, president of the Kenya-based China-Kenya Bicycle Manufacturing Company, told the Global Times that Chinese companies are generally welcomed by local Africans, as the Chinese help create jobs in the countries and boost local economies.

Lei Xiaolei, a human resources manager for the Tanzania project office of the China Railway Jianchang Engineering Company, told the Global Times that due to an unfamiliarity with the local rules and culture, his company received dozens of labor-related lawsuits 10 years ago when his company began operating in Tanzania.

"Salaries are paid monthly in China, but here in Tanzania workers are paid every week. There was a lot of chaos concerning payments, but things are improved, as we have tailored our policy to fit the local rules," he said.

Dong Baohua, a Shanghai-based lawyer specializing in labor law, told the Global Times that Chinese companies seeking investment in Africa should not be merely focused on making a profit, but also on understanding the local laws and how the local governments are functioning.

"Some companies falsely believe they can operate their businesses smoothly in Africa by simply building schools or making donations," Dong said.

"Though some local regulations may not be sound by themselves, understanding them would give Chinese companies a big edge in achieving success and assimilating into the local environment."