At the Web 2.0 Summit in San Francisco, Twitter's chief executive revealed to the Telegraph that negotiations with Google on renewing the partnership had failed so far.

“We [Twitter and Google] just can’t agree on what the appropriate value exchange is. And I don’t mean that in terms of dollars...There are all sorts of details that we couldn’t come to grips with.”

Last week Google announced that it would index updates from its new social network, Google+, as part of an overhaul of its search engine that will focus on real-time information.

“Our vision is to have google.com/realtime include Google+ information along with other realtime data from a variety of sources,” a Google spokesman said.

The firm also plans to introduce support for hashtags to Google+, a move that will be seen as a direct challenge to Twitter.