The European Court of Human Rights (ECHR) has voted narrowly against changing advertising rules which would have seen political organisations being allowed to buy time on British TV.
The case had been put forward by Animal Defenders International (ADI), who said its freedom of expression was not breached by denying it the chance to advertise on TV or radio.
The court ruled nine-eight not to change the ban, and said: "Overall, the court found that the reasons given to justify the ban were convincing and that the ban did not therefore go too far in restricting the right to participate in public debate."
It was suggested that if the ruling had gone the other way, it would have changed the laws on political advertising, and ultimately allow all groups and parties to participate in TV campaigns.
ADI brought forward the case in 2005, after an ad showing a juxtaposition of a girl, and a chimpanzee in chains in a cage was blocked by the Broadcast Advertising Clearance Centre, who suggested it would breach the 2003 Communications Act.