China shouldn't delay on economic reform, US Treasury chief Jack Lew says

United States Treasury Secretary Jack Lew said he would call on Chinese leaders this week to let markets determine the value of the yuan and to avoid postponing measures to overhaul their economy, even as growth falters.

"They obviously have to worry about their short-term economic situation," Lew said in an interview airing this weekend. "What they can't do is treat the long-term reforms as something they can just put off. They need to be serious about it."

Lew, who will meet Chinese officials on Tuesday in Beijing, said that while China had made some progress in loosening restrictions on its currency, "we've seen some very negative movement in the exchange rate in recent months".

Lew said he had been telling his counterparts to avoid becoming an alternative source of funding to Russia as US sanctions there begin to bite.

"We've been making the case consistently, wherever we go, that it's unacceptable for Russia to violate Ukraine's sovereignty," he said. "And that when we take actions and other countries in the world take action, it is important for there not to be backfill."

Russian President Vladimir Putin plans to open the door to Chinese money as US and European sanctions over Ukraine threaten to tip the economy into recession, two senior government officials said.