LONDON (Reuters) - Brewing giant SABMiller (>> SABMiller plc) reported weaker-than-expected profit and a dip in margins for the first half of its fiscal year, citing poor weather in China and intensified competition among retailers in Australia.

The world's second-biggest beer maker, with brands such as Miller Lite and Peroni, said earnings before interest, tax, depreciation and amortisation (EBITDA) were $3.28 billion in the six months to the end of September.

That was almost flat compared with the same period a year earlier and below the average forecast of $3.38 billion in a company-supplied consensus of 17 analysts.

Excluding the impact from the depreciation of currencies in Latin America and South Africa versus the dollar, SABMiller said EBITDA rose 3 percent.

The company's performance and strategy is the subject of great investor interest after an approach to buy Dutch rival Heineken (>> HEINEKEN) was rebuffed in September, breathing new life into speculation SAB is a target for the world's biggest brewer Anheuser Busch InBev (>> ANHEUSER-BUSCH INBEV).

Profit margins slipped by 30 basis points due to falling beer sales in China and parts of Europe as poor weather over the summer meant people drank less lager, the company said.

In Australia, increased competition among the retailers it supplies forced SABMiller to step up its promotional spending and trade terms as stores demanded better deals.

In the Asia-Pacific region - which accounts for 15 percent of revenue - EBITDA was 14 percent below consensus, according to analysts at RBC Capital Markets.

Last month, the brewer reported a 5 percent rise in first-half revenue, with volumes up 1 percent.

"Our underperform rating factors in our expectation of margin pressure that seems to be playing out," RBC said in a research note on Thursday.

SABMiller Chief Executive Alan Clark declined to comment on media reports this week that the company was planning to form a new company in Africa with Coca-Cola (>> The Coca-Cola Company).

Looking ahead, SABMiller said it expects trading conditions to remain challenging for the rest of its fiscal year but that it should continue to increase sales, find efficiencies across its business and invest in local markets. It expects raw material costs to rise by a "low single-digit" percentage rate in constant currency terms with some markets impacted by foreign exchange movements on imported raw materials.

(Editing by Jane Merriman and Pravin Char)

By Martinne Geller