A radical Muslim cleric alleged to have inspired the Fort Hood gunman has been praised in the past as “a preacher of peace” by a prominent SNP candidate with close links to Alex Salmond.

The FBI is investigating communications between Major Nidal Hasan, who killed 13 people at the US Army base in Texas, and Imam Anwar al-Awlaki, a US-born Muslim cleric now based in Yemen. Mr Awlaki has a large following in Britain and counts prominent mainstream Muslims among his supporters.

In 2006 Osama Saeed, who has been selected as the SNP candidate for Glasgow Central for the next general election, wrote that Mr Awlaki “preached nothing but peace”.

Last night Mr Saeed, who was researcher to Mr Salmond before he became the Scottish First Minister, distanced himself from Mr Awlaki, saying that he now felt “cheated” by the cleric.

Mr Saeed said: “I completely disagree with what he has said about Fort Hood, and a host of other matters which he has more recently written and spoken about.”

Mr Awlaki, 38, who on his blog described Major Hasan as “a hero”, has been a regular visitor to Britain and delivers frequent lectures to audiences here by video or via the internet.

Counter-terrorism sources said last night that Mr Awlaki was barred from entering Britain on security grounds, while the anti-extremist Quilliam Foundation said that he was “perhaps the most influential pro-jihadist ideologue preaching in English today”.

Despite his extremist reputation, the cleric has attracted widespread support from mainstream British Muslim groups and individuals.

Azad Ali, president of the Civil Service Islamic Society, wrote last November that Mr Awlaki was “one of my favourite speakers and scholars”.

Mr Ali, whose society’s patron is Sir Gus O’Donnell, the Cabinet Secretary, distanced himself from the cleric’s views last night. He said: “I reject them and disassociate myself from them completely.”

Mr Salmond came under attack two months ago over SNP links to the Scottish-Islamic Foundation, founded by Mr Saeed, after it emerged that the Scottish government had agreed to give the organisation taxpayers’ cash before it was legally established.

The Scottish government clawed back £128,000 paid to the foundation for a £1.4 million “IslamFest” event that was due to take place in Glasgow last June but was abandoned.

An SNP spokesman said last night: “Anwar al-Awlaki formerly expressed moderate views — his more recent comments are disgraceful and have been condemned by all right-thinking people, including Azad Ali and Osama Saeed. Any attempt to smear any individual in the UK over this would be appalling.”

While some people such as Mr Saeed now distance themselves from Mr Awlaki, his lectures continue to be circulated widely. The Times acquired DVDs of his lectures at two Islamic bookshops in East London, while Jimas, a registered charity based in Ipswich, offers downloads of his sermons on its website.

This year a video lecture by Mr Awlaki was delivered at the East London mosque under the banner “The End of Time” with a poster depicting New York in flames. The mosque said that an outside group had used its facilities for the event.

Mr Awlaki was born in New Mexico in 1971 and holds a US passport.

He was an imam at Rabat mosque in San Diego, where he encountered two of the September 11 hijackers, Nawaf al Hazmi and Khalid al Mihdhar.

The 9/11 Commission report said that Mr Awlaki “developed a close relationship” with the two hijackers but the cleric condemned the atrocities in interviews at the time.

The preacher moved from there to be an imam at Falls Church, Virginia, where he is reported to have first met Major Hasan.

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