Many stock markets around the world posted strong gains Tuesday as Americans headed to the polls to choose a new president for the world's largest economy.

U.S. share prices gained as much as four percent, European indexes rose as much as five percent, and key Asian markets also moved higher.

The gains come as a key measure of banks' willingness to lend to each other improved again.  Before recent declines in the "Libor" interest rate, international credit markets had been stalled, making the economic crisis worse.

Credit markets began flowing as governments around the world offered trillions of dollars in emergency aid to financial institutions and cut interest rates in a bid to restore bankers' confidence.  Australia cut its key interest rate today and the European Central Bank and the Bank of England are widely expected to slash rates on Thursday.  

But that news may be tempered by a new United Nations' report that says the financial crisis has spread to international trade, hitting developing nations that export commodities particularly hard.  

The U.N. report says a key measure of demand for trade, which tracks shipping costs, has fallen dramatically over the past few months.