SINGAPORE, July 4 Reuters The yen was firm on Tuesday but remained vulnerable to more weakness, as markets were on alert for signs of intervention, while the Australian dollar dropped after the country39;s central bank chose to stand pat on interest rates.

The Reserve Bank of Australia RBA held interest rates steady at 4.10, saying it wanted more time to assess the impact of past hikes, but warned further tightening might be needed to bring inflation to heel.

Across the currency markets, investors remained on watch for possible intervention by Japanese authorities to stem yen losses.

The yen last fetched 144.64 per dollar in Asian hours, but remained close to last week39;s eight month low of 145.07 per dollar that prompted Finance Minister Shunichi Suzuki to warn against excessive yen selling.

Earlier on Tuesday, Japan39;s top financial diplomat Masato Kanda said that officials were in close contact with U.S. Treasury Secretary Janet Yellen and other overseas authorities almost everyday on currencies and broader financial markets.

This is sending signals that a coordinated intervention may be coming as yen continues to hover above 144 per dollar, said Charu Chanana, market strategist at Saxo Markets.

A coordinated intervention usually has a longer lasting impact on the yen than a unilateral intervention would have.

Japan bought yen in September, its first foray in the market to boost its currency since 1998, as the Bank of Japan39;s pledge to retain ultraloose…