BEIJING - Some US senators have violated internationally accepted regulations by allowing a debate that seeks duties on Chinese imports, said Shen Danyang, a spokesman of the Ministry of Commerce, on Tuesday.

The spokesman said the yuan exchange rate was not to blame for China-US trade imbalance. It is unfair to use a controversial bill on so-called "currency manipulation" by China to transfer the US internal contradictions.

He added the global economy is in a sensitive period and needs a stable international monetary environment.

The US Senate voted Monday (local time) to allow a debate on the controversial bill amid strong opposition from China and US business groups.

The 79-19 vote opened a week-long debate on the bill, the last procedure before it is to be finally voted on the Senate floor. And for the bill to become law, it would still have to clear the House of Representatives and then be signed by President Barack Obama.