Israel's government has threatened to take "fierce and disproportionate" action after a group of Palestinians have taken to defacing the wall separating Israel from Palestinian territority.

"This group is funded by foreign anti-Israeli interests who have no wish to see peace in the region," said Israeli foreign minister Tzipi Livni in a tersely worded statement today. "How long can we stand by while these animals and their supporters overseas threaten the State of Israel?"

Livni was responding to reports that a group of West Bank Palestinian graffiti artists is offering to spray-paint personal messages for pay on the security wall in the West Bank.

"Graffiti is not art, and these paint cans and messages are a clear provocation against all those who love peace. We can not, and will not tolerate these actions," added Livni.

"It is clear that the terrorist state of Iran is behind these new graffiti initiatives, and we will not hesitate to punish all those who support terrorists activities against Israel," he said.

But Iranian President Mahmoud Ahmadinejad denied any involvement by his country.

 "Death to the Zionist oppressor. We will turn our nuclear weapons of peace into a deadly rain of punishment if they come to attack us. Just watch." he said.

Contacted at a Wal-Mart near his home in Texas, former US president George W Bush had an equally bleak message when informed about the graffiti.

"When we allow terrorists to take these spray cans and paint walls instead of houses, this is obviously the kind of thing that my administration when I was president, you know, we would not have allowed to just go on. And I think that Israel must do whatever it takes to prevent this kind of action from going on. It's just the American way."

There have been reports of Israeli troops massing near the West Bank, and as helicopter gunships loitered ominously overhead ordinary Palestinians fear that a fragile ceasefire holding between the two groups is in jeopardy.

"What will we do when the Israeli helicopters come and murder our children?" asked one woman?

"Yes it's true that this graffiti, I don't really care for it, it looks disgusting and makes the place look like a slum. But now the Zionists will come and kill us and nobody in the West will pay any attention. God will punish them."

The Palestinian graffiti provocateurs have set up a website at www.sendamessage.nl, and there are reports that the web server logs show the IP addresses of several computers located on networks known to be operated by the feared and respected Israeli secret police, the Mossad.

The White House had no comment today as US President Barack Hussein Obama and his family and staff were busy inside laughing it up with musician Stevie Wonder.