Sulaiman Abu Ghaith, the man believed to be Osama Bin Laden's son-in-law and spokesman, was arrested by US authorities last week and is to be tried in New York, it has been revealed. The al-Qaida militant had played a role in the 9/11 attack, said US officials.

Reports suggest he was intially arrested in Turkey and then deported to Jordan. With the help of local officials, US authorities picked up the militant in Jordan.

He is expected to appear in a federal court where he will face charges of conspiracy of killing Americans.

"Sulaiman Abu Ghaith held a key position in al-Qaida, comparable to the consigliore in a mob family or propaganda minister in a totalitarian regime. He used his position to threaten the United States and incite its enemies," said FBI Assistant Director-in-Charge George Venizelos.

Abu Ghaith is believed to be 47 years and was stripped of his Kuwaiti citizenship soon after the 2001 attack.

"To violent extremists who threaten the American people and seek to undermine our way of life, this arrest sends an unmistakable message. There is no corner of the world where you can escape from justice because we will do everything in our power to hold you accountable to the fullest extent of the law," said US Attorney-General, Eric Holder.

US authorities accuse Abu Ghaith of having worked alongside Bin Laden, who was killed in May 2011 by American forces in Pakistan, in al-Qaida's war against the US.

"Among other things, Abu Ghaith urged others to swear allegiance to bin Laden, spoke on behalf of and in support of al Qaida's mission, and warned that attacks similar to those of September 11, 2001 would continue," said the indictment, adding that the act of conspiracy "would and did murder United States nationals anywhere in the world".

The day after the 9/11 attack, Abu Ghaith appeared along with Bin Laden warning that a "great army is gathering against you," and urged the "nation of Islam" to fight against the "the Jews, the Christians and the Americans".

The news of the capture of Abu Ghaith was initially revealed by a senior Republican member of the House of Representatives Intelligence Committee, Peter King.

The former chairman of the House Committee on Homeland Security said in a statement: "I commend our CIA and FBI, our allies in Jordan, and President Obama for their capture of al-Qaida spokesman Sulaiman Abu Ghaith. I trust he received a vigorous interrogation, and will face swift and certain justice."