China said it is delaying for further study a plan to raise taxes for foreign manufacturers.

The plan, which would unify differing corporate income-tax rates for foreign and domestic companies, had been widely expected to be approved at the annual meeting of the national legislature currently under way, and implemented next year, according to the Wall Street Journal. Xie Xuren, director of the State Administration of Taxation, said in an interview that China still aims at merging the rates, a move required under China’s World Trade Organization commitments. He emphasized the government has examined the issue thoroughly, and "this year, we’re going to make more efforts to deepen that study."

Mr. Xie didn’t provide any terms when China might actually unify the rates. Foreign companies have united their efforts to delay the plan introduction, with about 54 U.S. companies recently signing a letter on the issue addressed to Chinese policy makers, according to people familiar with the matter.

Taxes turn out to be an important factor for foreign companies operating in China, since many are now profitable. Foreign manufacturers in China are obliged currently to pay 15% tax, much lower compared with 33% assessed on domestic companies. For non-manufacturing foreign companies this rate makes 24%. According to the government’s plan, all corporate tax rates would be unified, and make approximately 24%. That would make doing business in China more expensive for foreign manufacturers, while making domestic rivals more competitive in pricing.