Well-placed market sources indicated that Singapore Exchange and ASX are engaged in merger discussions.
Both exchanges face growing competition from new entrants.
In September both exchanges experienced strong growth. The four top exchanges in the FTSE Mondo Visione September 2010 analysis released earlier today were from the Australasian region.
The Philippine Stock Exchange led the pack with a 48.1% rise in September; HKEx came in second with growth of 25.6%, Singapore Exchange third with growth of 23.5% and ASX fourth with growth of 21.7%.
UBS is understood to be acting for ASX Ltd in the talks, with Morgan Stanley on behalf of the Singapore Stock Exchange.