Newly daubed graffiti on the Israeli wall cutting off the occupied West Bank lambasts US President Donald Trump and Facebook founder Mark Zuckerberg.

The work has appeared in recent days after secretive Australian artist Lushsux crowdsourced ideas for what to paint on the controversial separation wall, which in many areas cuts through the Palestinian territory.

But residents and visitors warned the art, much of which is not explicitly about the Israeli-Palestinian conflict, risks undermining the purpose of painting on the wall.

One painting depicts Trump penning a letter to the rapper Eminem, alongside a caption from his 2000 hit song "Stan" in which Eminem is stalked by a superfan.

The rapper attacked Trump in a widely publicised rap last week.

Another shows failed US Democratic presidential candidate Hillary Clinton asking "What happened?" -- which without the question mark is the title of her new autobiography. Next to her Trump says "I happened."

A third features Zuckerberg with red eyes and the caption: "The more of your data I gather, the more I understand what it means to be human."

Some of the ideas were crowdsourced, with the artist asking fans on Twitter for suggestions for captions.

He is currently asking fans which famous figure he should paint next, with suggestions ranging from another of Zuckerberg to Wikileaks founder Julian Assange.

Asked via Twitter why he chose to crowdsource his ideas, Lushsux told AFP he was "just trying to be social on social media".

In a previous interview, the Australian, whose identity is protected, has said he aims to be the "anti-Banksy" -- the British street artist whose artworks have been major hits all over the world.

- 'Here to paint memes' -

Lushsux, whose work often includes nudity, told Australia's ABC he wanted to "paint things that don't please everyone".

Israel began erecting the up to eight-metre wall during the second Palestinian intifada in the early 2000s citing security concerns, but Palestinians call it the "apartheid" wall.

It has long been a site for artists to highlight the Israeli occupation, with Banksy painting on it multiple times.

In March, he opened the Walled Off Hotel in Bethlehem, with all rooms looking out onto the wall.

Visitors said Wednesday they were concerned Lushsux's art didn't highlight Israeli policies.

"The wall risks becoming a street art gallery rather than actually politicising what it is about," Paul Saxton, a 30-year-old Briton visiting the site, told AFP.

"While it is great to look at -- these are fantastic works of street art -- maybe they could fit in any city rather than being in this place where there is a very deliberate issue."

Bethlehem resident Khader Jacaman said there was "no relationship" between the art depicting Clinton and Trump and the Palestinian cause.

"The Palestinian people don't want them to come, paint and go. Their (social media) followers don't do anything."

Lushsux brushed aside the criticism.

"To be fair, you have to have a very high IQ to understand the Israeli-Palestinian conflict," he told AFP.

"I'm not pushing a number required to solve it. I'm here to paint memes."

In 2004, an International Court of Justice advisory opinion called the wall illegal, but Israel rejects this and argues it is necessary to protect its citizens.

Around 400,000 Israelis live in settlements in the West Bank, which are considered illegal under international law.

Source: AFP