UPDATE 1-Macquarie sees H1 profit down 25 pct

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SYDNEY, Sept 6 (Reuters) - Macquarie Group Ltd (MQG.AX), Australia's top investment bank, said on Monday its profit would miss expectations by a wide margin as weak markets roil its key businesses.

Macquarie, which counts advisory and trading as its top businesses, said its six-month to September profit will fall by a quarter marking a return to profit decline. In April, Macquarie reported its first half-year profit rise in two years.

Macquarie's outlook is a tad weaker than its larger global rivals such as Goldman Sachs (GS.N), Morgan Stanley (MS.N) and investment bank units of JPMorgan (JPM.N) and Credit Suisse (CSGN.VX)

The bank, which gets almost half its revenue from Asia Pacific but is using its surplus to cash to expand in the United States and Europe, also said full-year profit should be broadly in-line with 2010.

That would miss full-year analyst estimates of a net profit of A$1.2 billion ($1.10 billion) and A$530 million for the half year, an increase of 14.3 percent and 10.6 percent respectively.\

This marks the first time Macquarie gave detailed indications of its profit expectations after warnings markets twice earlier that weak markets were hurting. (Reporting by Narayanan Somasundaram; Editing by Ed Davies)