* Euro underperforms after Greek referendum call spooks markets
* Traders on alert for further yen intervention from Japan
* Aussie dollar drops more than 2 pct after rate cut
By Nia Williams
LONDON, Nov 1 (Reuters) - The euro fell more than one percent versus the dollar and yen on Tuesday as investors cut exposure to the common currency after Greece’s unexpected call for a referendum revived uncertainty over how the euro zone will solve its debt crisis.
If the Greek people use the referendum to reject the latest bailout deal it would put the next aid tranche to Greece in jeopardy, moving it towards the brink of disorderly default, raising the risk of further contagion and financial market instability.
Those concerns weighed on riskier assets across the board including commodities and equities, while safe haven German Bunds rose.
The dollar index was last trading up 1.5 percent at 77.293, while the euro slid more than 1 percent versus the dollar to a low of $1.3671, triggering stops below $1.3680.
Traders cited Russian speculators and Swiss names selling the single currency in early European trade and said key support came in around $1.3650, the Oct. 18 low. A close below that level would leave the euro vulnerable to a test of its early October trough around $1.3145.
The risk-correlated Australian dollar fell more than 2 percent to a low of US$1.0294 after the central bank cut interest rates to 4.5 percent, with interest rate futures suggesting investors were braced for further easing.
The dollar dipped slightly versus the yen, however, having pulled back from a three-month high as the impact of Japan’s massive intervention on Monday faded a touch. It last traded down 0.1 percent at 78.12 yen , with market players wary of further yen selling by the Japanese authorities.
The single currency was also down 1.1 percent versus the yen at 107.05 , erasing some of the gains made during intervention.
“The Greek referendum is a real curve ball, nobody saw it coming and it injects a lot of uncertainty,” said Steven Saywell, head of FX strategy at BNP Paribas.
“We had a lot of dollar buying yesterday from the Japanese Ministry of Finance which has added to the dollar bullish view as well as the setback in equity markets. These are all factors coming together to add to this risk-off sentiment.”
Some analysts said investors would be wary of buying the dollar too aggressively given a two-day Federal Reserve meeting that concludes tomorrow and key U.S. jobs data due on Friday. Any hints that the Fed is considering further monetary easing to boost the flagging economy could drive the greenback lower.
Trading in dollar/yen steadied after Japan’s yen-selling intervention on Monday. It backed off the three-month high of 79.55 yen hit the previous day but held well above levels seen before intervention of around 75.65 yen or so.
The dollar briefly surged around 60 pips or so to an intraday high of 79.10 yen during Asian trading on Tuesday but quickly gave back its gains, and traders said the rise was unlikely to have been caused by intervention.
Bank of Japan money market data suggested that around 7.7 trillion yen ($98.7 billion) was sold in Monday’s intervention, well above previous record of 4.5 trillion yen set in August.
After the August intervention the dollar erased all its gains within a few days and hit a fresh record low just over two weeks later.
Although investors remained alert for any signs of further intervention from the Japanese authorities, some analysts said they saw the dollar gradually easing lower.
“My feeling is that the strategy seems to be to come in once very aggressively. I imagine from here we will see a gradual grind lower,” said Derek Halpenny, head of currency research at Bank of Tokyo-Mitsubishi in London.
“It’s possibly not going to retrace as quickly as in August. Intervention has come at a time when the dollar is going to continue to perform well as risk aversion escalates and Europe becomes an even bigger mess.”
Many market players doubted that Japan would adopt a Swiss-style floor for dollar/yen given such a move was unlikely to be endorsed by the G20 or the G10. The G20 is meeting later this week in Cannes, France.