Kenyan politicians have adopted amendments to a controversial media bill despite an opposition walk out and international concern about press freedom.

The bill, which was passed in October but sent back to parliament with presidential changes, will see journalists and media outlets policed by a special quasi-government body.

It also calls for huge fines that could force the shutdown of news organisations.

Beryl Aidi, an official from the Kenya Human Rights Commission, said it was "bad news", arguing that the most contentious elements of the bill remain despite presidential changes, including the power to impose up to 20 million Kenyan shillings ($234,000) in fines.

"It does not improve the bill ... it does not improve the situation," she told AFP news agency on Thursday.

The bill has sparked furious reactions from Kenya's vibrant independent media, with front pages declaring that democracy and free speech were under attack.

The US-based Committee to Protect Journalists (CPJ) has said the amended bill still contained "draconian provisions".

Politicians from the opposition Coalition for Reforms and Democracy walked out of parliament as the bill was debated and voted upon.

"If we do not do this with deep thought, we will be setting a dangerous precedent," opposition MP Jakoyo Midiwo told parliament. "We will also be opening up the window for a future rogue president."

Crippling fines

Possible individual fines for journalists were cut from one million to 500,000 Kenya shillings (5,775 dollars), but that is an amount still crippling for most.

"That is still way too high," Aidi added.

Earlier this week United Nations human rights experts urged Kenya to reject the media bill, warning it could severely rein in democratic freedoms in the country.

If implemented, it "could lead to restrictive interpretations that would unduly limit the rights to freedom of association, and opinion and expression," UN expert Frank La Rue said in a statement.