Indianola, Iowa (CNN) Bernie Sanders said Sunday in Iowa that he would support working with Russia and Iran to combat the ISIS, taking a slightly more hawkish stance than he did earlier in his campaign.

"We have different points of view ... but Russia has got to join us. We are concerned about Iran, but Iran has to join us. We have concerns about Saudi Arabia, but Saudi Arabia has to join us," Sanders said during a speech at Simpson College. "If all over the world these attacks are taking place, the world has got to come together."

The Vermont senator, who has not outlined a detailed plan to defeat ISIS, has long stressed cooperation to combat terror and stressed that the United States should not take the lead on the effort.

His willingness to work with Russian President Vladimir Putin, a world leader who's had a rocky relationship to the U.S., makes it unclear how Sanders -- someone who is notably against further foreign entanglements -- would work with Russia without getting more involved in Syria.

In an interview after his speech on Sunday night, the 2016 Democratic presidential candidate said it is possible to "destroy ISIS" when countries work together.

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