The U.S. Department of Defense is considering “potential improvements in cruise missile defense” as part of its ballistic missile defense review, according to a nominee for a high-level Pentagon job.

“If confirmed, I look forward to participating in this review and examining potential additional capabilities,” said John Rood, President Donald Trump’s pick to be undersecretary of defense for policy. Capitol under clouds

Rood’s comments came in response to a written question from the Senate Armed Services Committee, which held a hearing on his nomination Nov. 16. The committee asked him whether NATO defenses should be increased to counter Russia’s newly deployed, nuclear-armed, ground-launched cruise missiles, as well as its air- and sea-launched cruise missiles.

The ballistic missile defense review is due to be finished by year’s end. Trump called for the review in a January memorandum to Defense Secretary Jim Mattis.

DoD and the Trump administration have said little about the ongoing review. But in the fiscal year 2017 defense authorization act, Congress told DoD to conduct a “missile defeat” strategy review that includes both ballistic and cruise missile defenses.

“Given the growing size and sophistication of the threat to the U.S. homeland, we clearly need a missile defense system that can handle a larger volume of threat missiles and effectively deal with their increased sophistication,” Rood wrote. “We also need to evaluate options for better sensor coverage, the ability to deal with countermeasures, and take steps to deal with growing cruise and hypersonic missile threats.”

In his written answers, Rood also endorsed providing lethal security assistance to Ukraine to help it defend against Russia.

But Rood’s nomination ran into turbulence at the committee hearing, as Sen. John McCain (R-Ariz.), the panel’s chairman, accused him of “ducking” questions about whether he would recuse himself from matters involving his latest employer, Lockheed Martin [LMT]. McCain urged Rood to clarify his position in writing.

“Mr. Rood, I hope we can clear that up,” McCain said. “It’s just not something that should be difficult. You should not be making decisions that are related to your previous employment or would affect the fortunes of” a previous employer.

Rood, who has been senior vice president at Lockheed Martin International, told the senators he was “trying to provide a clear answer.” For example, he said he would avoid participating in deliberations on Lockheed Martin exports but that he would be involved in arms-related policy discussions with other countries.

McCain and Sen. Elizabeth Warren (D-Mass.) both reiterated their concerns about the number of DoD appointees who hail from the top five defense companies.

“As I have said before, my reservations grew out of early consultations I had with the [Trump] administration about a number of potential nominations,” McCain said in his opening statement. Rood is “the last of the individuals we discussed at that time. Therefore, from this point forward, I will not support any further nominees with that background.”