* LSE discussing next month's planned upgrade
* Clients have asked for caution
* The exchange has planned an extra test
By Luke Jeffs
LONDON, Oct 15 (Reuters) - The London Stock Exchange said on Friday it was in talks with its largest investment bank clients over whether it should postpone a technology upgrade scheduled for next month after a glitch last week.
The London-based stock market had planned to move its main UK equities order book from its current system to faster, more flexible technology on Nov. 1. But its largest trading customers have become concerned about this tight deadline after a glitch in a dry-run last week and have this week urged the exchange to delay, possibly to its contingency date of Nov.15.
"We are ready to go, and we want to move sooner rather than later, but we are getting feedback from customers. We need to be sure the vast majority of our members are ready and these discussions are ongoing," Tony Weeresinghe, the LSE's director of global development told Reuters.
The LSE moved its pan-European trading system Turquoise to its Millennium technology platform on Oct. 4, in what it said was a test run for the transition of its larger UK equities trading business next month.
The migration was smooth except for a glitch on Oct. 5, when Turquoise was down for an hour at the start of trading. But clients have asked the exchange this week to err on the side of caution with regard to the UK order book roll-out.
"A delay is not ideal, but it would be more embarrassing for the LSE if they went live and there were problems," said the head of electronic trading at a large investment bank.
"Working in partnership with our clients, we need to look to see if everyone is ready for the LSE Group move. Turquoise was one thing, but none of our members want to be out of the main market when it moves to Millennium," Weeresinghe said.
The LSE has scheduled an extra test run on Oct. 30 ahead of the UK order book migration.
"Following this additional rehearsal, and working with our customers to ensure readiness, the LSE Group will update the market on the migration timetable," it said in an emailed statement. (Editing by Will Waterman)