US will send 560 more soldiers to Iraq
The increase will bump up the total authorised number of US forces in Iraq to more than 4,600, further deepening Washington's military involvement as the lead force behind the international anti-IS coalition.
"I am pleased to report today that... we agreed for the United States to bolster Iraqi efforts to isolate and pressure Mosul by deploying 560 additional troops," Carter said in Baghdad, referring to Iraq's IS-held second city.
"The additional troops will provide a range of support for Iraqi security forces, including infrastructure and logistical capabilities at the airfield near Qayyarah," the Pentagon said in a statement on Carter's announcement.
The Pentagon chief made the announcement within hours of landing in Baghdad on an unexpected visit to hold talks with Prime Minister Haider al-Abadi.
The ultimate goal, he said, was "the recapture of all of Iraqi territory by the Iraqi security forces, but of course Mosul is the biggest part of that."
The duo were met with the Canadian Defence Minister who also made the unexpected journey to Baghdad a few hours later, The New Arab correspondent in Iraq confirmed.
It comes just two days after US-backed government forces recaptured an airbase to the south of Mosul – adding to a string of victories expected to aid in the long-awaited operation to push the Islamic State group from Mosul.
Prime Minister Haider al-Abadi described the Qayyarah airbase as an "important base to liberate Mosul" calling on the city's residents "to get ready for the liberation of their areas."
Several important cities across the two countries, including Ramadi in Iraq and al-Shadadi, a town in northeastern Syria previously considered a strategic IS stronghold have been recaptured in recent months – more than two years after the militants seized large swaths of land in Iraq and Syria.
But as the anti-IS coalition powered through militant-held cities in the region, all efforts have since refocused on Mosul, Iraq's second-largest city located about 360 kilometres (225 miles) northwest of Baghdad, which fell to militants during the summer of 2014.