NEW YORK, Aug 12 (Reuters) - Lawyers for a New York man accused of pledging allegiance to al Qaeda in Yemen are asking a judge to suppress statements he made to the FBI after he was placed on a "no-fly list" by U.S. authorities.

But Manhattan federal prosecutors in a court filing on Friday said any statements Brooklyn-born Wesam El-Hanafi, 36, might have made were voluntary and not coerced.

El-Hanafi was arrested in April last year and charged with conspiracy to provide material support to al Qaeda militants.

Prosecutors have said El-Hanafi bought seven digital Casio watches through Internet seller Amazon.com to send to militants in Yemen and that the alarms in the watches could be used as triggers for a bomb.

At issue are statements El-Hanafi made to U.S. law enforcement in January and February 2010 in the United Arab Emirates upon finding out he had been placed on the U.S. "no-fly" list.

"He was placed on the no-fly list, and deceived into believing that submission to an interview with the FBI was the only mechanism to secure his removal from the list," his lawyers argued in court papers to U.S. District Judge Kimba Wood.

Prosecutors counter that El-Hanafi was free to leave at any point during the interviews and called defense arguments that they were unconstitutional "extravagant."

"Even if, as El-Hanafi claims, he was told at the close of the February 2010 interview that if he did not cooperate with questioning, he would risk losing the opportunity to receive the agents' assistance, this would not amount to coercion," prosecutors said.

Prosecutors also said it was not necessary to advise El-Hanafi of his Miranda rights --a statement where police advises a suspect of their right to remain silent, that any statement may be used as evidence against them and that they have the right to have an attorney present-- because he was never formally arrested or restrained.

El-Hanafi was charged along with another man, Sabirhan Hasanoff, 35, a dual U.S. and Australian citizen. Hasanoff has also been fighting the charges in court papers.

El-Hanafi and Hasanoff have pleaded not guilty to the charges.

A trial is scheduled for Jan. 23, 2012. They face up to 75 years in prison if convicted.

The case is U.S. v. Wesam El-Hanafi and Sabirhan Hasanoff, U.S. District Court, Southern District of New York, No. 11-162.

For Hasanoff: David Ruhnke and Joshua Dratel.

For El-Hanafi: JaneAnne Murray and Justine Harris.

For U.S.: Brendan McGuire and John Cronan Assistant U.S. Attorneys, U.S. Attorney's Office for the Southern District of New York.

(Reporting by Basil Katz)

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