BEIJING – China is calling for a new global currency to replace the dominant dollar, showing a growing assertiveness on revamping the world economy ahead of next week’s London summit on the financial crisis.

The surprise proposal by Beijing’s central bank governor reflects unease about its vast holdings of U.S. government bonds and adds to Chinese pressure to overhaul a global financial system dominated by the dollar and Western governments. Both the United States and the European Union brushed off the idea.

The world economic crisis shows the “inherent vulnerabilities and systemic risks in the existing international monetary system,” Gov. Zhou Xiaochuan said in an essay released Monday by the bank. He recommended creating a currency made up of a basket of global currencies and controlled by the International Monetary Fund and said it would help “to achieve the objective of safeguarding global economic and financial stability.”

China has long been uneasy about relying on the dollar for the bulk of its trade and to store foreign reserves. Premier Wen Jiabao publicly appealed to Washington this month to avoid any response to the crisis that might weaken the dollar and the value of Beijing’s estimated $1 trillion in Treasuries and other U.S. government debt.

For decades, the dollar has been the world’s most widely used currency. Many governments hold a large portion of their reserves in dollars.

But the financial crisis has highlighted how America’s economic problems – and by extension the dollar – can wreak havoc on nations around the world. China is in a bind. To keep the value of its currency steady – some say undervalued – the Chinese government has to recycle its huge trade surpluses, and the biggest, most liquid option for investing them is U.S. government debt.