* SSEC -0.1 pct; CSI300 0.0 pct; HSI +0.7 pct
* Wall Street soars to new highs overnight
* Investors cautious waiting for outcome of regulatory investigation
SHANGHAI, Dec 8 (Reuters) - Hong Kong stocks reached a five-week high on Thursday morning, after Wall Street set new records ahead of a European Central Bank policy meeting later in the day.
But China stocks were little changed, as better-than-expected November trade data was countered by another fall in foreign exchange reserves, which heightened concerns of accelerated capital outflows and further yuan depreciation.
The benchmark Hang Seng index added 0.6 percent at the end of the morning session, to 22,948.38 points, while the Hong Kong China Enterprises Index gained 1.0 percent, to 9,929.20 points.
The blue-chip CSI300 index was unchanged at 3,475.30 points, while the Shanghai Composite Index slipped 0.1 percent, to 3,220.53 points.
Risk appetites in China were curbed after data late Wednesday showed foreign exchange reserves fell nearly $70 billion last month to the lowest level in nearly six years, as the central bank struggled to prop up the yuan's value.
Resource shares advanced, despite the generally cautious mood.
Steelmaker Baoshan Iron & Steel Co Ltd and Wuhan Iron and Steel jumped in the morning session on the heels of regulatory approval for their merger plan.
Zhang Yanbin, an analyst at Zheshang Securities, said mainland markets were under correction after recent regulatory moves on insurers' leverage buy-outs.
In the Hong Kong market, which often takes cues from Wall Street, nearly all sectors rose.
Whether the rally is sustainable relies largely on the outcome of the ECB meeting. It was widely expected that the ECB might start preparing investors for an eventual tapering of its stimulus.
Reporting by Jackie Cai and John Ruwitch; Editing by Richard Borsuk