Travelers watch the announcement boards in Euston rail station during the busy morning rush hour on Aug. 9, 2019, in London. The train network was hit by major delays Thursday after all services out of London Euston were suspended due to a(CNN)09 - A suspected failure in Britain's National Grid network has led to a power cut across large areas of London and southeast England, UK Power Networks said Friday. "We're aware of a power cut affecting a large area of London and South East. We believe this is due to a failure to National Grid's network, which is affecting our customers," UK Power Networks tweeted. Transport for London has also confirmed to CNN that parts of its train network were affected following the power outage on Friday evening, but that power had been restored and service was expected to be back up and running shortly.