A 19-year-old Colorado woman who has admitted that she had planned to travel overseas to join the Islamic State in Iraq and the Levant (ISIL), has been sentenced to four years in a US federal prison.

In a statement to the court on Friday before sentencing, Shannon Maureen Conley expressed gratitude to the FBI for "potentially saving my life" by intervening to arrest her, and said she rejected the violent ideology espoused by some Muslims.

"I believe in true Islam, where peace is encouraged," Conley, a Muslim convert, said.

Conley, from suburban Denver, struck up an online relationship last year with a Tunisian man, identified as Yousr Mouelhi, who said he was a member of ISIL, according to an FBI arrest warrant affidavit.

"During their communications, Conley and Mouelhi shared their view of Islam as requiring participation in violent jihad," according to the plea agreement reached with federal prosecutors.

Conley, a certified nurse's aid, went to a US Army Explorers camp in Texas and had firearms and first-aid training in preparation for waging war against those she considered infidels, court papers showed.

Federal agents met with Conley several times in an attempt to dissuade her from joining ISIL.

But Conley told them she planned to marry Mouelhi and join the fighters to "correct the wrongs against the Muslim world," even though she knew it was illegal, the FBI affidavit said.

Conley had faced up to five years in prison, but prosecutors agreed not to seek the maximum penalty because of her guilty plea and co-operation with investigations.

She has been held without bond since federal agents arrested her in April at Denver International Airport as she prepared to board a plane bound for Germany.

In September, Conley pleaded guilty in Denver federal court to one count of conspiracy to provide material support to ISIL, designated by the US government as a foreign terrorist organisation.

Source: Reuters