Army Secretary Eric Fanning said the biggest impact of even a short-term continuing resolution would would be the service's inability to ramp up its European reassurance and deterrence efforts.

"Our [European Reassurance Initiative] ERI funds increase pretty substantially from this year to last," Fanning told Defense News in a Sept. 27 interview. "The Army is being asked to do a lot of new things in Europe, move some force structure there, rotational, and that will be delayed in the first quarter," he said one day prior to Congress passing a budget deal that included a three-month continuing resolution that funds the fiscal 2017 budget at 2016 levels.

President Obama's last budget request more than quadrupled the amount of overseas contingency operations (OCO) money funneled into ERI. The $3.4 billion in fiscal 2017 funding is part of an effort to deter Russia's military aggression in Eastern Europe and to bolster allies' defense capabilities. And $2.8 billion of the ERI is Army money.

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The Army, for one, plans to deploy a heavy brigade in Europe – a "heel-to-toe" armored brigade combat team (ABCT) – in theater 24/7 on a rotational basis on top of the Stryker brigade and infantry brigade already in Europe. The biggest chunk of the ERI funding – $2 billion – will go to that deployment.

The service has yet to decide exactly how to disperse the brigade in Europe and Fanning said that the decision is being worked at Defense Secretary Ash Carter's level. However, the decision could get held up in the wake of a CR, he added.

The ERI would also fund $727 million for "increased presence" while $50 million would go toward building "partner capacity" and $89 million would expand the scope of 28 joint and multinational exercises held in Europe annually.

And $1.8 billion of ERI funding is planned to pay for prepositioned equipment to include an entire ABCT static set of equipment in addition to the already established "activity set" – separate sets of equipment outside of prepositioned stocks – that builds out a brigade combat team.

Delaying continuous rotations of heavy brigade units in countries like Bulgaria, Romania, Poland, and the Baltics, could send a dangerous message to Russia and its leader Vladimir Putin that the US is not prepared to reassure the vulnerable allies along its border and Russia may get the mistaken impression the US is unable to deter its behavior along the bordering countries, the thinking goes.

The Army was looking at rotations beginning on Oct. 1 with plans for another unit to arrive in April 2017.

The service may also have to slow its plans to increase the lethality of its Stryker armored personnel carriers by adding a 30mm cannon. The engineering change was ordered due to an urgent requirement coming from Europe.

US Army Europe Commander Lt. Gen. Ben Hodges has said on numerous occasions that he can't get the up-gunned Strykers fast enough. Yet, the plan is to field the first Strykers in Europe to the 2nd Cavalry Regiment – currently outgunned by Russian counterparts – in 2018.

Fanning also noted that the Army's plan to plus up some of its training efforts will have to slow down due to the CR and if it extends into the second quarter of the fiscal year, some of the funding the Army wants to put in place to execute recommendations from the National Commission on the Future of the Army could be affected.

The Army has not come out with a report to Congress yet on what recommendations it will implement from the commission's findings, but service leaders have stated on several occasions that it would implement the majority.

The service has indicated that about 50 recommendations are achievable at little to no cost, but several the Army would implement require a significant boost in funding such as retaining four attack battalions in the Army National Guard, which equates to 72 AH-64 Apache helicopters and would cost $62.1 million. The Army also asked to retain the 11th Combat Aviation Brigade, requesting $305.4 million to do so.

The commission was established by Congress to study the future force and structure of the Army and came out with a report with 63 comprehensive recommendations for the service in January.