WASHINGTON (Reuters) - President Donald Trump’s nominee to be the director of national intelligence pledged on Tuesday to support thorough investigation of any Russian efforts to influence the 2016 presidential election, seeking to reassure lawmakers worried that partisan politics might interfere with a probe.

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“I think this is something that needs to be investigated and addressed,” former Republican Senator Dan Coats told the Senate Intelligence Committee during his confirmation hearing to be the top U.S. intelligence official.

Coats, 73, a former member of the intelligence panel, also promised that it would have full access to all of the documents and other materials needed for an investigation.

“I have no intention of holding anything back from this committee,” Coats said.

Trump denounced intelligence agencies for their assessment that Russia sought to influence the election on his behalf, prompting concerns about his support for them. Trump has also repeatedly praised Russian President Vladimir Putin, leading some in Washington worry that he might not take a hard enough line in dealings with Moscow.

In his opening statement, Coats addressed that concern by listing activity by Russia, along with that of China and North Korea, as among the main challenges faced by the United States.

“Russia’s assertiveness in global affairs is something I look upon with great concern, which we need to address with eyes wide open and a healthy degree of skepticism,” Coats said.

The Office of the Director of National Intelligence was created after the Sept. 11 attacks to oversee all 16 U.S. intelligence agencies and improve communications among them.

One concern about Coats was his record on the U.S. use after the 2001 attacks of so-called enhanced interrogation techniques, such as waterboarding, which are widely seen as torture. In 2015, he was one of the few lawmakers who opposed legislation sponsored by Republican Senator John McCain that made the use of such techniques illegal.

Coats promised that he would follow the law, saying he voted against that legislation because he wanted “to at least have a discussion” about the best way to proceed if intelligence agencies wanted to obtain crucial information quickly.

Coats also strongly defended U.S. government surveillance programs, though he said he would “do everything I can” to publicly disclose an estimate of the number of Americans caught in the crosshairs of internet surveillance programs intended to target foreigners.

But he stopped short of guaranteeing such a disclosure, which privacy advocates in Congress have requested for years and said is necessary to properly debate possible reforms to a surveillance law that expires at the end of 2017.

Although he was ambassador to Germany under President George W. Bush, Coats would be the first director of national intelligence who has not spent most of his career in the military, in intelligence agencies or as a diplomat.

Coats, who is popular with Democrats and his fellow Republicans, is expected to be easily confirmed.