Last week, Labour MP Tom Watson asked the Electoral Commission to investigate claims by the BBC's Robert Peston that former News of the World editor Coulson was paid thousands of pounds by his former employer while working as David Cameron's communications chief.
Watson called on the commission to probe whether the payments and benefits should have been declared because they amounted to a "political donation". However, the commission said last night that it was taking no "further action" on the matter.
Meanwhile, a 71-year-old man believed to be former News of the World managing editor Stuart Kuttner was released on bail yesterday evening as part of the phone hacking probe.
Kuttner was bailed for the first time on August 3 after being arrested the previous day on suspicion of conspiring to intercept communications, as well as bribing police officers to leak sensitive information.
"The man was arrested on August 2 and bailed to a date in August, and he has now been bailed to a date in September," a Met police spokesman said.
Rupert Murdoch and his son James are expected to face further questioning under oath by a judge at the High Court about the phone hacking scandal at the News of the World, and the session could potentially be broadcast live to the public.