The Australian and New Zealand dollars weakened further following the Reserve Bank of Australia's decision to cut interest rates.
There is growing speculation that the Swiss National Bank (SNB) has set a new target for the country's currency.
The Swiss franc hit a two-week low against the euro and the dollar, on talk that the Swiss National Bank was intervening to weaken the currency.
Russia's ruble is under renewed pressure after the Central Bank of Russia shocked markets with a rate cut, sending the currency to a 2015 low.
The Swiss franc fell past 1.05 francs per euro for the first time since the Swiss National Bank dumped its 1.20 francs cap.
The U.S. dollar inched higher against the yen and was steady to the euro on Thursday after a Federal Reserve statement which.
The dollar rose against a basket of currencies on Wednesday, recouping some of the previous day's sharp losses.
Todd Elmer, Currency Strategist at Citi, says investors are wondering what the surprise move by Singapore's central bank means for broader asset markets and future policy direction.
The Swiss franc continued to show volatility as the country's central bank signaled that it had not given up intervening in currency markets.
The euro rose against the dollar before a meeting of the U.S. Federal Reserve that may push back expectations for an interest rate rise.
The euro regained a foothold in early deals in London, investors choosing to take some profit on two days of steep losses.
The price of the Russian ruble fell sharply against the U.S. dollar Monday after fighting increased in the eastern part of Ukraine.
The euro fell to fresh 11-year lows against the dollar after the ECB said on Thursday it would pump a trillion euros into the euro zone economy.
The euro hit a fresh 11-year low after Draghi announced the launch of an open-ended expanded monthly 60 billion euro bond-buying program.
The currency war is being played like a chess match, but that will eventually change, veteran trader Art Cashin told CNBC.
The yen rebounded against the dollar after the Bank of Japan stood pat on monetary policy.
The dollar hit a one-week high against the yen after China growth data was not as bad as many had feared, curbing demand for the safe-haven Japanese currency.
The European Central Bank could take its boldest steps yet to revive the euro zone's moribund economy.
New Zealand's Prime Minister, John Key, says structural reform is needed in the euro zone to boost the region's economy.
New Zealand's Prime Minister John Key says the low oil price is positive for consumers.