Asian currencies have fallen following the shock launch of six missiles by North Korea into the Sea of Japan.

This morning the yen was down to 114.92 against the dollar, while the South Korean won was at 949.43 to the greenback.

North Korea launched five short-range Scud type missiles which fell several hundred kilometres off the coast of Japan. A sixth long range missile, with the capability to strike US and Australian soil, failed within the first minute of launch.

Regional stocks as well as currencies fell due to the uncertainty.

Japan's Nikkei 225 Stock Average dropped 0.7 per cent and South Korea's Kospi index fell 2.1 per cent.

The dollar, euro and pound all gained, as did gold, as investors looked for a safe haven.

"This is a big deal, and is very bad for all of north Asia," Sean Callow, a currency strategist at Westpac Banking, told Bloomberg.

"We just don't know how far North Korea may go."

However, Minoru Shioiri, senior foreign exchange manager at Mitsubishi UFJ Securities, was more optimistic when he spoke to the Associated Press.

"The yen's outlook is basically bullish against the dollar with an interest-rate hike by the Bank of Japan expected as early as next week,"

he said

"If the North Korean issue doesn't aggravate further in the coming days, the dollar will likely resume falling gradually against the yen."