Corruption is the biggest threat to China's Communist Party, President Xi Jinping said on Monday, in a clear warning that the ruling party is resolved to tackle a long-running problem that is now entrenched in many strata of Chinese society.

The United States imposed sanctions on a senior member of the Hungarian government for alleged corruption, the U.S. Treasury said on Tuesday, a move Budapest said it would challenge when President-elect Donald Trump takes power.

A senior Hungarian government official close to Prime Minister Viktor Orbán was hit Tuesday with U.S. sanctions for his alleged involvement in corruption in Hungary, a rare step against a sitting official in an allied country.