Trading in the biggest shares listed on the London Stock Exchange has been delayed for more than an hour because of a technical problem.
Shares in the FTSE 100 and FTSE 250 indices were affected by the issue, although smaller stocks were trading.
The LSE said it was investigating a “potential trading services issue”, and an update was due at 09:15.
The last time the market failed to open on time at 08:00 was in June 2018, when it was delayed by an hour.
David Madden, an analyst at CMC Markets, said that he had not received any official notice, and no time frame when the issue would be resolved.
Outages on the stock exchange are relatively common. This is the second time in 18 months that the London Stock Exchange has suffered a technical fault. Last time, the exchange was down for an hour.
Craig Erlam, senior market analyst at foreign exchange company Oanda, said the outage was due to “a potential trading services issue”.
“Unfortunately, I don’t think we can blame Brexit for this one but maybe I’ll be proven wrong,” he said.
The FTSE 100 had been expected to open higher after a bruising few days amid the raging US-China trade war.
London traders may be missing out on healthy gains. France’s CAC 40 index ticked up 0.8 per cent in early trading, the pan-European Euronext 100 rose 0.8 per cent, and Germany’s Dax rose 0.9 per cent.
Neil Wilson, chief market analyst at trading platform Markets.com, said the outage “leaves people sitting on their hands” in London.