Iran-backed Shiite fighters in Iraq now number up to 100,000 fighters, the first-known estimate of their size, according to the US military. It was earlier reported that Iran’s Syria-based commander is preparing to retake the Iraqis city of Mosul.

In what appears to be a deepening role played by Iran in the fight against Islamic State (IS, ISIS/formerly ISIL), the forces’ estimates range anywhere from 80,000 up to 100,000, according to spokesman Colonel Chris Garver, who confirmed the figure to Fox after it was first floated by the head of US Central Command, Army General Joe Votel in late July, according to the Tampa Bay Times.

According to Garver, not all Shiite fighters making up the Popular Mobilization Forces (PMF) are Iran-backed – that figure usually stands at about 80,000. The rest of the figure is a mashup of Sunni tribal fighters from Iraqi provinces of Anbar and Nineveh, also rising up against the IS threat.

READ MORE: US military warns victories in Iraq and Syria not end of ISIS

The new estimates coincide with Moscow’s confirmation that it is now launching anti-IS operations in Syria from an Iranian military base for the first time on Tuesday. Tu-22M3 and Su-34 bombers took off from the Hamedan Airbase, striking IS and Al-Nusra Front facilities in the provinces of Aleppo, Deir ez-Zor and Idlib. They were covered by Su-30m and Su-35 fighters, which took off from Russia’s Syria-based Kheimim Airbase.

Aside from the PMF, another Iranian outfit – the Revolutionary Guard’s Quds Force – is now forecast to play a massive role over in Iraq’s Mosul, which has been in IS’ grip since 2014.

The State Department conceded for the first time on Thursday that it delayed making a $400 million payment to Iran for several hours in January “to retain maximum leverage” and ensure that three American prisoners were released the same day.

For months the Obama administration had maintained that the payment was part of a settlement over an old dispute and did not amount to a “ransom” for the release of the Americans. Instead, administration officials said, it was the first installment of the $1.7 billion that the United States intends to pay Iran to reimburse it for military equipment it bought before the Iranian revolution that the United States never delivered.

But at a briefing on Thursday, John Kirby, the State Department spokesman, said the United States “took advantage of the leverage” it felt it had that weekend in mid-January to obtain the release of the hostages and “to make sure they got out safely and efficiently.”

Republicans opposed to the nuclear deal President Obama reached with Iran have described the payment as ransom and a further sign of his administration’s feckless dealings with Tehran.

http://www.nytimes.com/2016/08/19/world/middleeast/iran-us-cash-payment-prisoners.html?_r=0