* Yen dips on wariness about whether Japan will take action
* Japan PM: will take firm action on currencies if needed
* Traders await Bernanke's speech, U.S. GDP data
(Updates prices, adds quote, details)
By Jessica Mortimer
LONDON, Aug 27 (Reuters) - The yen dipped against the dollar and the euro on Friday as wary nervous speculators trimmed long positions and Japan's prime minister reiterated a threat to take steps to stem the currency's steady rise.
Prime Minister Naoto Kan said he would take firm action on currencies when needed and that he would meet Bank of Japan Governor Masaaki Shirakawa when the central bank chief returns from an overseas trip. [ID:nTKZ006504]
The yen stayed in negative territory but did not extend losses after the comments. Analysts and traders said Kan seemed to play down the prospect of imminent action but they remained wary with the currency so close to 15-year highs versus the dollar.
Caution ahead of a speech by Federal Reserve chairman Ben Bernanke at the Fed's annual retreat in Jackson Hole at 1400 GMT and U.S. gross domestic product data at 1230 GMT also kept major currency pairs within tight ranges.
"There doesn't seem to be any urgency to take action and Kan's comments will do little to stop dollar/yen moving lower," said BNP Paribas currency strategist Ian Stannard.
At 0916 GMT, the dollar was up 0.3 percent against the yen JPY= at 84.72, pulling off an intraday low of 84.27 yen as traders said an earlier media report that Kan was to hold a news conference sparked profit-taking in dollar/yen short positions.
But the pair stayed close to a 15-year low of 83.58 yen hit on trading platform EBS earlier this week and still below 85.00 yen, which had been seen as a level of concern for Japanese authorities. The euro EURJPY=R rose 0.3 percent to 107.72 yen.
"We have had such a strong move followed by more and more talk about possible intervention risk that it is natural people would want to trim long positions," said Anders Soderberg, currency strategist at SEB in Stockholm.
The euro was steady against the dollar at $1.2716 EUR=, off a six-week low of $1.2588 hit earlier this week when it was hit by concerns about the health of some euro zone countries.
Traders said the euro held within a tight range ahead of U.S. GDP data and Bernanke's speech. They cited bids around $1.2690, capped by offers around $1.2750.
The Fed announced plans earlier this month to boost a flagging economy by reinvesting money from maturing mortgage bonds in government debt and investors will look for clues on possible further moves.
SEB's Soderberg said the market was priced for a downward revision to U.S. GDP after recent weak data. A particularly weak number may cause knee-jerk dollar falls but this would probably be short-lived if global equities fell in response, prompting investors to seek the safety of the greenback, he said.
Despite the risk of possible action by Japanese authorities to curb yen strength such as yen-selling intervention or monetary easing by the Bank of Japan, some traders and investors say the yen could test a record high of 79.75 yen to the dollar, hit in April 1995, later this year.
The fate of the yen will depend on the overall trend of the U.S. economy rather than the possibility of Bank of Japan intervention, Michiharu Maeda, general manager of Dai-ichi's separate account management division told Reuters in an interview on Thursday.
"We believe that there is a big chance of the BOJ intervening by itself ... but the impact could be limited as the central bank's efforts could result in creating more chances for the market to sell (the dollar against the yen)," Maeda said.
A euro zone source familiar with the situation said on Thursday that joint central bank intervention to stem the rise of the yen was not likely. [ID:nLDE67P16B] <^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ PDF on Japan's yen puzzle: r.reuters.com/nef47n Q+A-Will Japan intervene to curb yen's rise? [ID:nTOE67O07Q] BOJ FOCUS on chance of monetary easing [ID:nTOE67N07Z] Why the yen may remain strong [ID:nTOE67B078] ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^>
(Additional reporting by Masayuki Kitano in Tokyo)