AN advertising campaign by Donald Trump, the US property tycoon, attacking Alex Salmond's support for wind farms, will this week be condemned as "misleading" by the UK Government's advertising watchdog.

The Sunday Herald has learned that the Advertising Standards Authority (ASA) will on Wednesday publish a damning ruling on adverts that appeared in Scottish newspapers last December. The adverts linked the First Minister's backing for wind power to the Scottish Government's decision to free the man convicted of the Lockerbie bombing, Abdelbaset Ali Mohmed al-Megrahi.

The ruling, the second against Trump's anti-wind farm campaign in Scotland, has been welcomed by environmental groups and wind lobbyists. But it has prompted the Trump Organisation, which confirmed the ruling against it, to berate the ASA for being "disorganised, inefficient and wasteful".

The adverts featured a picture of a forest of wind turbines on a hill overlooking a motorway in California under the heading "Is this the future for Scotland?" Below was a photograph of Salmond smiling and giving the thumbs up.

"Tourism will suffer and the beauty of the country is in jeopardy," said the text. "This is the same mind that backed the release of terrorist al-Megrahi 'for humane reasons' after he ruthlessly killed 270 people on Pan-Am Flight 103 over Lockerbie."

The adverts, which ran in the Aberdeen Press and Journal and the Dundee Courier on December 14, prompted 21 complaints to the ASA, claiming it was misleading and the reference to al-Megrahi offensive.

The ASA has concluded that the claim tourism would suffer "could not be substantiated", while the picture of California wind farms was "misleading", it said.

On both counts Trump has broken advertising rules, and the ASA has banned the adverts from appearing again. It told Trump "not to make claims unless they could be substantiated with robust evidence and not to use misleading imagery".

According to online reports, the ASA ruled readers were likely to find the al-Megrahi reference "distasteful" but not offensive. Hence it didn't breach advertising standards.

Alex Doyle, of pro-wind group, yes2wind, welcomed the ruling. "There are often a lot of myths regarding wind energy," he told an online magazine. "The misleading Trump advert is a prime example."

Lang Banks, head of environmental group WWF Scotland, said: "The advert was pretty distasteful, and it's now been shown to be factually wrong too."

Trump has launched legal action against the Scottish Government's decision last month to give the go-ahead to a wind farm off the coast from his Aberdeenshire golf course.

George Sorial, executive vice- president and counsel for the Trump Organisation, said advocates of wind farms were "deluded and ignorant" and were "promoting the deliberate mutilation of their own economy, environment, coastline and countryside."

He said the advert had been approved in advance by the Committee of Advertisement Practice (CAP), a body that works with the ASA.

"We actually wanted the content to be much stronger because Scotland is facing an economic and environmental meltdown," he said.

"The fact that the ASA has now clearly contradicted the advice of the CAP demonstrates how disorganised, inefficient and wasteful these agencies are. "

The ASA did not comment on the outcome of its investigation into the Trump adverts. Last September, the ASA upheld complaints about earlier anti-wind farm adverts by Trump.