NEW YORK (Reuters) - The dollar should extend its relentless advance against virtually every currency except the yen next week as global recession fears keep investors fleeing risky assets for the relative safety of the greenback.

A global market rout on Friday that battered stocks from Tokyo to New York and sent commodity prices tumbling kept investors in a state of almost perpetual panic. They reacted by yanking money out of higher-yielding assets to salt it away in dollars, a valued safe-haven in times of turmoil.

The Japanese yen has also surged to multiyear highs as investors who borrowed it to buy higher-yield assets unwound those positions and poured the money back into Japan, a trend that's also set to continue in the week to come.

Analysts say even a hefty interest rate cut, which the Federal Reserve is expected to deliver at a midweek policy meeting, won't blunt these forces, which have lifted the dollar to multiyear highs against the euro, sterling and high-yield emerging market currencies such as the South African rand.

While global lending has loosened up a bit in recent days, the cost of credit for banks, businesses and consumers remains high, and the threat of a deep global growth slump looms.

"Nobody knows how bad the recession is going to be but the longer credit markets stay locked up, people will assume the worst," said Win Thin, senior currency strategist at Brown Brothers Harriman in New York.

That means more dollar gains, he said, particularly because global investors had bet so heavily against it in recent years when credit was easy to come by. US interest rates were low and the global economy was growing by leaps and bounds.

That started to reverse in August as the credit crisis worsened, and now investors are being forced to pull money out of emerging stocks and bonds, commodities and investments in a host of currencies once considered more attractive than the dollar, including the euro, sterling and Australian dollar.

Over the last three months, the euro has lost about 21 percent against the dollar, while sterling is down about 22 percent after hitting a six-year low below $1.53 on Friday.

Stephen Jen, global head of currency research at Morgan Stanley in London, said emerging market currencies are especially vulnerable. Bets in their favour grew so big that he says there is still far more unwinding to come.

"We're only in the third inning of the global emerging currency moment," he said, adding "we are far away from the point" where these currencies hit bottom.

Woes in emerging markets will also hurt the euro and sterling, Jen said, as European and British banks are five times as exposed to these markets as their counterparts in the United States and Japan.

The safest currency bets are exposure to the dollar, yen and Swiss franc, which until now has underperformed its fellow low-yielders, say Morgan Stanley currency strategists. Coordinated intervention to arrest the dollar and prop up the yen remains a risk, analysts said, particularly if the Japanese currency falls below 90 yen per dollar.

But even here, the risks are legion. If intervention efforts failed, Thin said, currency moves could accelerate and become even more disorderly.