ANKARA, Turkey — Even as it discouraged Iran from joining diplomatic talks on how to defeat the Islamic State militant group, the United States could not outline Friday what other nations have volunteered to contribute to a worldwide effort against the insurgency that has overtaken a third of Iraq and Syria and threatens to upend the Mideast.
Secretary of State John Kerry, in Turkey to press its leaders on hardening its borders against extremist traffic and funding, said it's not appropriate for Iran to be at the discussions, given its support for the very government in Syria whose brutality helped fuel the Islamic State group.
But after more than a week of meetings with top NATO and Mideast officials, Kerry refused to say precisely how a global campaign that is being pieced together by the U.S. would succeed in destroying the Sunni extremist movement that some believe is even more dangerous than al-Qaida. France has said it wants Iran to participate.
Kerry said "no one has called me and asked me" whether France should invite Iran to the diplomatic talks set for Monday in Paris on helping Iraq fight off the Islamic State group. The militancy is among Sunni rebels groups that have battled for three years Syrian President Bashar Assad, who is surviving in part with Iran's help.
"Under the circumstances, at this moment in time, it would not be right for number of reasons," Kerry said. "It would not be appropriate, given the many other issues that are on the table with respect to their engagement in Syria and elsewhere."
He said Iranian forces have fought rebels in Syria, and accused Tehran of being "a state sponsor of terror" in some areas of the world.
Kerry also refused to clarify how nations are willing to participate in President Barack Obama's strategy to obliterate the insurgents' vision of creating an extremist caliphate that could encroach on much of the Mideast.
He noted that France, for example, has made clear it is willing to use deadly force against the militants in Iraq, as has Obama. And Kerry said that as many as 40 countries have offered various levels of support, from humanitarian aid to cracking down on illicit cross-border funding and fighters flowing to the insurgents, to providing intelligence and supplies to rebels in Syria and security forces in Iraq.
The U.S. is also seeking partners on a planned military campaign that could broaden ongoing airstrikes against extremists in Iraq and extend them into Syria.
"There are other countries that are currently making up their minds, making decisions," Kerry told reporters after a day of meeting with Turkish President Recep Tayyip Erdogan and other top officials. "It's just not appropriate to start laying out as we are in the process of talking to all these countries, which country is doing what."
He described himself as "very pleased" with the talks so far.
"I am comfortable this will be a broad-based coalition with Arab nations, European nations, the United States, others contributing to every single different facet to what President Obama laid out as a strategy, and fully embracing the need to degrade and destroy ISIL," Kerry said, using an acronym for the insurgency.
Earlier, at the start of a meeting with Kerry, Turkish Foreign Minister Mevlut Cavusoglu cited "challenges and threats" in Iraq and Syria.
He did not mention the Islamic State group by name and did not respond to a shouted question about why Turkey refused, a day earlier in Saudi Arabia, to join the U.S. with a coalition of Mideast nations. Pledging to curb the extremists' resources, the coalition also promised to repudiate their ideology, provide humanitarian aid to their victims and potentially contribute to a military campaign.
Turkey sits on the front line of the extremist group's battleground in Iraq and its haven in Syria and already has assisted refugees and cracked down on some suspicious cross-border traffic from both countries. But Turkey has resisted publicly endorsing a new global strategy to defeat the Islamic State group, which has kidnapped 49 Turkish citizens, including some diplomats.
The U.S. is being careful not to push Turkey too hard as it grapples with trying to free its hostages. The Turks were kidnapped from their consulate in the northern Iraqi city of Mosul when it was overrun by Islamic State militants in June.
The extremists also are holding several Americans hostage. As payback for more than 150 airstrikes that Washington has launched against them in Iraq since last month, the militants have beheaded two U.S. journalists who were working in Syria.
Senior U.S. officials who briefed reporters traveling with Kerry said Ankara already has been working against the Islamic State group, including by recently stopping about 6,000 people from entering Turkey and deporting 1,000 more who were deemed suspicious. But one of the U.S. officials said Turkey's borders remain extremely porous.
Turkey has taken in an estimated 1 million Syrian refugees since the Syrian civil war began in March 2011.
It's not clear whether Turkey will be willing to contribute to the potential military campaign that the new coalition is planning. The effort is likely to include training and equipping Syrian rebels and Iraqi forces, providing intelligence, and expanding airstrikes against extremists in Iraq and potentially into Syria.
Because of its location, Turkey could be an ideal staging place for allied fighter jets and drones that would launch the airstrikes. But the U.S. officials said there currently are no plans to do so.
The U.S. officials all spoke on condition of anonymity because they were not authorized to be named in briefing reporters.
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