Twitter, which has suffered a series of outages this week, warned that there could be more problems amid heavy World Cup traffic.

Jean-Paul Cozzatti, a Twitter engineer, said on the Twitter blog that the micro-blogging service's problems this week were due to an internal network being over-capacity.

Cozzatti said Twitter was doubling capacity and rebalancing traffic on the network to redistribute the load.

When Twitter goes down, a picture of a whale - known as the "fail whale" - appears on Twitter.com and Cozzatti said his engineering team was hoping for fewer appearances by the creature.

"You may still see the whale when there are unprecedented spikes in traffic," he said.

"For instance, during the World Cup tournament - and particularly during big, closely-watched matches (such as tomorrow's match between England and the USA) - we anticipate a significant surge in activity on Twitter.

Brought to you by AAP © 2024 AAP