Trump told reporters last week he would press Putin on election meddling and also discuss Syria and Ukraine during their meeting.
The Pentagon is already reviewing the impact of withdrawing some of the 35,000 active-duty American troops in Germany, The Washington Post reported last month.
Much, of course, depends on the president's mood, which is rarely good during worldwide conferences where he bristles at what he considers the unfair economic and security alliances the United States constructed in the wake of WWII and the Cold War.
Trump and Putin will likely also discuss two arms control pacts - the INF Treaty and the New Strategic Arms Reduction Treaty (New START), Huntsman said, declining to address whether they might strike a deal on either pact, which are planks of U.S.
Trump has expressed scorn for the alliance and is expected to upbraid European NATO members for not spending enough on their own defense.
Last month, a dour Trump stomped through the G7 summit in Canada, suggesting Russian Federation be readmitted to the elite economic group, despite having been expelled for invading neighboring Ukraine and annexing Crimea. He referred to Chancellor Angela Merkel, saying: "And I said, 'You know, Angela, I can't guarantee it, but we're protecting you and it means a lot more to you than protecting us 'cause I don't know how much protection we get by protecting you".More news: Pompeo to visit Mexican president-elect; discuss immigration, trade
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Also in the teleconference, Kay Bailey Hutchison, the US envoy to the North Atlantic Treaty Organization (NATO), said Russian Federation would be a key topic at the NATO summit in Belgium next week.
Other than with NATO Secretary General Jens Stoltenberg, Trump has no other bilateral meetings now scheduled. Thousands more rotate into other European countries temporarily. Poland, for instance, has put forth a proposal for the U.S.to build permanent military bases. The U.S. spends about 3.5 per cent.
He added that Trump hopes the meeting "can help reduce tensions and lead to constructive engagement that improves peace and security around the world because you can't solve problems if you're not talking about them", but said: "the ball really is in Russia's court".
The White House declined to say if and how Trump might punish the countries.
As part of this plan, Trump could mothball US bases in Europe and shift most resources spent there and in the Atlantic to the Indo-Pacific region, where China and Iran pose real threats to America-and against which NATO is irrelevant.
In the call, a senior administration official defended the decision for the one-on-one interaction, stating that it is the direction Trump has deemed best.