Sunni volunteers take part in military training as they prepare to fight against militants of the Islamic State, in the town of Amriyat al-Falluja in Anbar province, January 8, 2015. (Photo by Reuters/Stringer)

Sunni volunteers take part in military training as they prepare to fight against militants of the Islamic State, in the town of Amriyat al-Falluja in Anbar province, January 8, 2015. (Photo by Reuters/Stringer)

Sunni volunteers take part in military training as they prepare to fight against militants of the Islamic State, in the town of Amriyat al-Falluja in Anbar province, January 8, 2015. (Photo by Reuters/Stringer)

Sunni volunteers take part in a parade as they prepare to fight against militants of the Islamic State in the town of Amriyat al-Falluja in Anbar province, January 8, 2015. (Photo by Reuters/Stringer)

Sunni volunteers take part in military training as they prepare to fight against militants of the Islamic State, in the town of Amriyat al-Falluja in Anbar province, January 8, 2015. (Photo by Reuters/Stringer)

Sunni volunteers take part in a parade as they prepare to fight against militants of the Islamic State, in the town of Amriyat al-Falluja in Anbar province, January 8, 2015. (Photo by Reuters/Stringer)

Iraqi security forces take part in training, as they prepare to fight against militants of the Islamic State, at a training camp on the outskirts of Mosul January 10, 2015. (Photo by Azad Lashkari/Reuters)

Sunni volunteers take part in a parade as they prepare to fight against militants of the Islamic State, in the town of Amriyat al-Falluja in Anbar province, January 8, 2015. (Photo by Reuters/Stringer)

Members of the Iraqi security forces take part in training, as they prepare to fight against militants of the Islamic State, at a training camp on the outskirts of Mosul January 10, 2015. (Photo by Azad Lashkari/Reuters)

Sunni volunteers take part in a parade as they prepare to fight against militants of the Islamic State, in the town of Amriyat al-Falluja in Anbar province, January 8, 2015. (Photo by Reuters/Stringer)

Sunni volunteers carry weapons during a parade as they prepare to fight against militants of the Islamic State, in the town of Amriyat al-Falluja in Anbar province, January 8, 2015. (Photo by Reuters/Stringer)

Iraqi security forces take part in training, as they prepare to fight against militants of the Islamic State, at a training camp on the outskirts of Mosul January 10, 2015. (Photo by Azad Lashkari/Reuters)

Sunni volunteers take part in a parade as they prepare to fight against militants of the Islamic State, in the town of Amriyat al-Falluja in Anbar province, January 8, 2015. (Photo by Reuters/Stringer)

Members of the Iraqi security forces train as they prepare to fight against militants of the Islamic State, at a training camp on the outskirts of Mosul January 10, 2015. (Photo by Azad Lashkari/Reuters)

Members of the Iraqi security forces take part in training, as they prepare to fight against militants of the Islamic State, at a training camp on the outskirts of Mosul January 10, 2015. (Photo by Azad Lashkari/Reuters)

Members of the Iraqi security forces take part in training, as they prepare to fight against militants of the Islamic State, at a training camp on the outskirts of Mosul January 10, 2015. (Photo by Azad Lashkari/Reuters)

Members of Iraqi security forces chant slogans during training, as they prepare to fight against militants of the Islamic State, at a training camp on the outskirts of Mosul January 10, 2015. (Photo by Azad Lashkari/Reuters)

Members of the Iraqi security forces take part in training, as they prepare to fight against militants of the Islamic State, at a training camp on the outskirts of Mosul January 10, 2015. (Photo by Azad Lashkari/Reuters)

Members of the Iraqi security forces take part in training, as they prepare to fight against militants of the Islamic State, at a training camp on the outskirts of Mosul January 10, 2015. (Photo by Azad Lashkari/Reuters)

Iraqi Defence Minister Khaled al-Obeidi (L) speaks to members of Iraqi security forces during training, as they prepare to fight against militants of the Islamic State, at a training camp on the outskirts of Mosul January 10, 2015. (Photo by Azad Lashkari/Reuters)

Members of the Iraqi security forces take part in training, as they prepare to fight against militants of the Islamic State, at a training camp on the outskirts of Mosul January 10, 2015. (Photo by Azad Lashkari/Reuters)

German Defence Minister Ursula von der Leyen (2nd R) greets Kurdish forces female recruits at the Zeravani Training Centre in Bnaslava near Arbil, north of Iraq January 12, 2015, who are being trained by the German armed forces, Bundeswehr. (Photo by Maurizio Gambarini/Reuters)

German Defence Minister Ursula von der Leyen (R) visits the Zeravani Training Centre in Bnaslava near Arbil, north of Iraq January 12, 2015, where Kurdish forces are being trained by the German army, Bundeswehr. (Photo by Maurizio Gambarini/Reuters)

German Defence Minister Ursula von der Leyen (background R) visits the Zeravani Training Centre in Bnaslava near Arbil, north of Iraq January 12, 2015, where Kurdish forces are being trained by the German army, Bundeswehr. (Photo by Maurizio Gambarini/Reuters)