Update: 13.40 BST: BT says the issue has now been fixed and services have been restored.
Sorry if you're unable to access some websites this morning on BT Broadband, we're investigating the cause and will update you all soon
— BTCare (@BTCare) July 21, 2016
We've contacted BT, with a spokesperson responding, "We apologise to those BT customers who had problems connecting to some internet services this morning. Internet usage is now back to normal for consumer and small business customers. A small number of larger businesses may still be experiencing some limited internet access. Engineers should have these fixed soon.
"The issue, which affected BT and other providers, was due to Telehouse North, one of our internet connection partners in the docklands, suffering power issues. The issue affected less than five percent of our customers’ internet usage, and BT took immediate action to minimise these issues by redirecting traffic."
Telehouse North has also issued the following statement: "We are aware that there has been an issue with the tripping of a circuit breaker within Telehouse North that has affected a specific and limited group of customers within the building. The problem has been investigated and the solution identified. Our engineers are working with our customers on the resolution right now. We will release updates in due course."
Yesterday's troubles were caused by 'power issues' at one of BT's internet connection partners’ sites in London.