A social media complaint over the toilet habits of Israeli Prime Minister Benjamin Netanyahu's dog has spiralled into vicious online muck-slinging between the sons of the incumbent and former premiers.

The fur began to fly when the Netanyahu family's 10-year mixed-breed bitch Kaiya allegedly pooped in a Jerusalem park while being walked by eldest son Yair Netanyahu.

A neighbour who said she witnessed the act wrote on Facebook that when she challenged Netanyahu to clean up after the animal, he made an obscene gesture with his middle finger.

Adding to pressure on Yair Netanyahu was an online attack by Molad, an Israeli think-tank critical of Netanyahu's right-wing government.

In an item entitled "Five things you didn't know about heir to the throne Yair Netanyahu," it slams his lifestyle, particularly the huge cost to the taxpayer of his round-the-clock protection and government car with driver and the fact that at 25 he lives with his parents in their official Jerusalem residence.

Stung, Netanyahu junior responded with a Facebook post suggesting Molad publish similar critiques of sons of former premiers.

Among them he named Omri Sharon, who spent four months in prison for funnelling illegal contributions to the election campaign of his father, the late prime minister Ariel Sharon.

He also implies that former premier Ehud Olmert's son Ariel has a homosexual affair with a Palestinian, referring to "his interesting relations with a Palestinian man and its significance for the security of the country".

Netanyahu's post concludes with emojis showing a pile of dung and the finger gesture.

Olmert's Facebook response displays some humour, as well as anger.

"Hi Yair Netanyahu, I am the secret son of Olmert, the homo son, the one who lives with a Palestinian," he writes.

"In fact, this story is totally false. I love women, I live with one of them and we have a daughter."

Slamming the "racism and homophobia" in Netanyahu's post, he adds: "Unlike you... I actually work for my living. I also, on principle, try to pick up my dog's poop."

- 'Kaiya Law' -

Netanyahu critics attack Yair as a grown man living in the prime minister's residence despite having no official role.

They say his parents are grooming him for future political power in an attempt to establish a ruling dynasty.

They also complained about his presence at official functions during the visit of US President Donald Trump in May.

On meeting Trump and his wife Melania, Yair told them he could empathise with their young son Barron and the pressure of growing up in the media's glare.

Kaiya the dog, who was adopted from a shelter, first made headlines of her own in 2015 when she bit an Israel lawmaker and the husband of a cabinet minister during a reception at the Netanyahu residence.

She was sent to quarantine kennels in accordance with the law.

The premier said the experience brought home to him "flaws incompatible with logic and compassion" in Israel's public health regulations, which mandate that dogs who bite, even if they have received all the necessary inoculations, be confined for 10 days.

On Wednesday, parliament approved the first reading of a bill unofficially known as the "Kaiya Law" which would allow a dog who has bitten to be confined at home rather that sent to kennels, media reported.

source: AFP