In a service announcement to clients, the company said it was experiencing a third party global technical issue.
This came as a major IT outage impacted companies across the globe.
The LSEG outage also meant that company updates were not being published to markets through its Regulatory News Service, while signs of disruption in one of the world's busiest financial centres emerged as London trade got underway.
Reuters contacted several of the world’s biggest banks to check the status of their trading activities, including JPMorgan, HSBC, Goldman Sachs and Barclays but none of the lenders had an immediate comment.
One London-based trader said several multilateral trading facilities were being affected by the outage, leaving some clients unable to trade.
"We are having the mother of all global market outages," the trader added.
During Asian trading hours, LSEG said its news services were experiencing a global technical issue that prevented news from being published on its platform.
LSEG said other services across the group, including the London Stock Exchange, continued to operate as normal.
Separately, it said it was experiencing technical problems publishing its spot and forward prices for currencies at 0600 GMT.
"This is currently under investigation and we will provide further information as soon as we can," LSEG said in a message to clients seen by Reuters.
LSEG was not immediately available for comment when contacted by Reuters in London. Its shares opened 0.6% lower in early London trade.
Elsewhere, a cyber outage related to an issue at global cybersecurity firm Crowdstrike (CRWD.O) and Microsoft (MSFT.O) hit media, retailers, banks airlines and telecoms companies across Australia and New Zealand on Friday.
