Apple is in talks for a $700 million takeover of Twitter, it's being reported.

With Google and Microsoft said to be eying the micro-blogging service, and Twitter turning down a $500 million offer from Facebook last year, it's a lot of money and attention for a site that's yet to make money.

ValleyWag, citing a source "who's plugged into the Valley's deal scene and has been recruited by Apple for a senior position", says the two companies are in "serious negotiations".

Apple is said to be hoping to tie the deal up in time for an announcement at the WWDC developer event at the start of June.