(Adds details of software issue, comments and share performance)
Nov 16 (Reuters) - A software problem forced Australia's stock exchange to halt trading 20 minutes after opening on Monday and it plans to reopen on Tuesday, the bourse operator ASX Ltd ASX.AX said.
The issue affected trading of multiple securities in a single order and led to inaccurate market data, ASX said.
"ASX and its technology provider Nasdaq have identified the root cause and a resolution path to fix it," it said in a statement, adding that the issue wouild be resolved overnight.
The market will re-open as usual on Tuesday at 10 a.m. (2300 GMT Monday), it said.
The problem came to light as the ASX's new equity market trading platform went live on Monday, despite more than a year of testing by customers, third parties, the ASX and Nasdaq NDAQ.O .
ASX "accepts responsibility", Dominic Stevens, chief executive officer Dominic Stevens said.
"The obligation to get this right and provide a reliable and resilient trading system for the market rests with us," Stevens said.
In the short while that the market was open, shares ended the day 1.2% higher, its highest close since the end of February.
Neighbouring New Zealand faced nearly a week of cyber attacks in August that crashed its website and impacted trading.