(Updates with comments, details, Zoellick interview)
By Shinichi Kishima
TOKYO, Oct 24 (Reuters) - Japanese exports rose for a sixth straight month in September thanks to robust demand in Asia, although the prospect of a slowing U.S. economy and weak demand at home tempered any optimism for the months ahead.
Exports rose 6.9 percent in September from a year earlier, Ministry of Finance data showed on Thursday, although economists noted that last year's figures had been affected by disruptions following the September 11 attacks in the United States.
The export rise pushed up the trade surplus by 1.1 percent to 1.055 trillion yen ($8.47 billion). It was the seventh rise in a row, albeit much smaller than in previous months due in part to relatively perky imports.
On a month-on-month basis, exports fell 2.3 percent from August in seasonally adjusted terms.
"Generally, the focus is on exports because this has been the driving force behind the recovery over the past nine months. Clearly the slowdown in export growth is quite a concern," said Richard Jerram, economist at ING Financial Markets in Tokyo.
Imports rose 8.8 percent in September from a year earlier and 6.5 percent from a month earlier, but economists say it is too early to say domestic demand has turned higher as near-record unemployment and sagging wages subdue consumer spending.
Indeed, import strength in September was due in part to a 282 percent rise in aircraft purchases.
"The per-unit price of aircraft is very high, so this item tends to fluctuate a lot," a Finance Ministry official said.
EXPORT-LED RECOVERY
Japan's economy expanded for the first time in five quarters in the three months to June, but the recovery has been heavily reliant on exports due to stagnant consumption and capital investment at home.
Underpinning Japan's exports were shipments to China, the second-biggest destination for Japanese products, which rose 39.7 percent in September from a year earlier.
For the six months to September 30 -- the first half of the current fiscal year -- exports to Asia surged 14.9 percent to a record 11.4 trillion yen, underscoring the increasing importance for Japan's economy of growth in its Asian neighbours.
Japan signed its first free trade agreement with Singapore this year and is pursuing others, prodded to a great extent by the growing clout of China as an Asian competitor.
"China is starting to move on these issues and Japan has gotten very nervous," U.S. Trade Representative Robert Zoellick told Reuters in an inteview on the sidelines of an Asia Pacific Economic Cooperation (APEC) meeting in Mexico.
He criticised Japan's approach to negotiating free trade agreements, saying it wanted to leave agriculture out of pacts.
CARS STAND OUT
Semiconductors, steel and automobiles were the main growth areas for exports to Asia in September.
Automobile exports to the United States, which have been the brightest spot in Japan's recovering economy, rose 17.1 percent.
"Against a background of a gradually recovering global economy, shipments are increasing in a wide range of Japanese products, but autos in particular were strong," the Finance Ministry official said.
The volatile exchange rate of the yen, still nearly 10 percent above January levels, remained a worry.
The trade data showed that the average dollar/yen exchange rate in September was 118.99 yen to the dollar. This was a 0.8 percent rise in the yen from a year earlier, when the dollar plummeted in the wake of the September 11 attacks.
The yen was around 124 yen to the dollar on Thursday.
Nissan Motor President Carlos Ghosn said in a CNN interview aired on Thursday that the yen had helped the company in 2001, though it had been relatively stable against the dollar in 2002.
Japan's third-largest automaker said on Wednesday it expected a record half-year group operating profit of 348 billion yen for the six months to September 30, up 84 percent from last year.
Economists said exchange rate volatility over the past year meant volume figures were important to judge trade trends.
On a volume basis, exports were up 9.0 percent in September from a year earlier, and imports were up 12.9 percent.
"I think it's more sensible to look at the volume figures," said ING's Jerram.
"If you do that, there is still growth, but it's now quite slow growth. Realistically, the big benefits from external demand look to be over. So now the focus is on whether any domestic drivers will start to improve to keep the recovery running."