Edward Snowden, who became the most wanted fugitive in the world after he leaked government secrets and fled the country, tells “Nightly News” anchor Brian Williams: “If I could go anywhere in the world, that place would be home.”

In the exclusive interview, Snowden said amnesty or clemency would be for the public and the government to decide. He said that he sees himself as a patriot, while also revealing that he plans to ask Russia to extend his asylum.

WATCH: Brian Williams hosts live special with Snowden analysis at 11 p.m. ET

“I’ve from Day One said that I’m doing this to serve my country,” Snowden said in excerpts broadcast Wednesday on “Nightly News.” The extended, wide-ranging interview with Williams airs Wednesday at 10 p.m. ET on NBC.

Play Facebook

Twitter

Embed autoplay autoplay Copy this code to your website or blog

Snowden said his desire to return to his homeland is foremost in his mind. “I don’t think there’s ever been any question that I’d like to go home,” he said.

But asked whether he would make a deal to return, Snowden said: “My priority is not about myself. It’s about making sure that these programs are reformed — and that the family that I left behind, the country that I left behind — can be helped by my actions.”

The United States charged Snowden with theft and two counts of espionage after he revealed the breadth of National Security Agency surveillance programs, including the bulk collection of telephone and Internet data from Americans.

The interview with Williams was conducted in Moscow last week after months of preparation and is Snowden’s first with a U.S. television network. Snowden maintained that the surveillance programs violated the Constitution on an enormous scale, and he said that he acted to serve his country.

“Had that not happened, had the government not gone too far and overreached, we wouldn’t be in a situation where whistleblowers were necessary,” he said.

Speaking of his own decision to leak the information and flee the country, he said, ““I think it’s important to remember that people don’t set their lives on fire, they don’t say goodbye to their families — actually pack up without saying goodbye to their families — they don’t walk away from their extraordinary — extraordinarily comfortable lives — I mean, I made a lot of money for a guy with no high school diploma — and, and, and burn down everything they love for no reason.”

"So when people ask, ‘Why are you in Russia?’ I say, ‘Please ask the State Department.’”

Regarding Russia’s grant of temporary asylum, which he said expires Aug. 1. Snowden told Williams, “If the asylum looks like it’s going to run out, then of course I would apply for an extension.”

In interview excerpts released earlier, Snowden blamed the State Department for stranding him in Russia. He said that he had a flight booked to Cuba and on to Latin America, but “the United States government decided to revoke my passport.”

Play Facebook

Twitter

Embed autoplay autoplay Copy this code to your website or blog

He was stuck in the transit zone of the Moscow airport for weeks before the Russian government granted asylum.

“So when people ask, ‘Why are you in Russia?’ I say, ‘Please ask the State Department,’” Snowden said.

Secretary of State John Kerry, in a live interview on TODAY, said that the government would be “delighted” for Snowden to return to the United States and face the justice system. Kerry said that a true patriot would “stand up in the United States and make his case to the American people.” He also called Snowden’s claims “pretty dumb.” In a later interview on MSNBC, Kerry described Snowden as a coward and traitor.

“What he’s done is expose for terrorists a lot of mechanisms which now affect operational security of those terrorists and make it harder for the United States to break up plots, harder to protect our nation,” he said.

In an earlier excerpt from the NBC News interview broadcast Tuesday, Snowden fought back against critics who dismissed him as a low-level hacker — saying he was “trained as a spy” and offered technical expertise to high levels of government.

Related

Snowden Says the U.S. Stranded Him in Russia

Kerry Calls Snowden's Comments 'Pretty Dumb'

Snowden: 'I Was Trained As a Spy'

Who is Edward Snowden?

Edward Snowden: A Timeline

Snowden: #Traitor or #Patriot

President Barack Obama once called him a “29-year-old hacker” not worthy of “scrambling jets” to capture.

Yet, Snowden, now 30, described himself as a technical expert who has worked for the government at high levels, including for the Defense Intelligence Agency and undercover for the CIA and NSA.

He said he was a lecturer at the DIA’s Joint Counterintelligence Training Academy, where “I developed sources and methods for keeping our information and people secure in the most hostile and dangerous environments around the world.” The DIA confirmed that Snowden, as a contractor, had spoken at three of its conferences.

Play Facebook

Twitter

Embed Kerry: ‘Pretty dumb’ Snowden blames US for stranding him 6:40 autoplay autoplay Copy this code to your website or blog

Two intelligence sources told NBC News that Snowden had worked for the CIA at an overseas station in information technology and communications.

The CIA declined comment.

Snowden, a former government contractor, later worked for private intelligence companies inside NSA outposts in Japan and Hawaii. While working for the contractors, he downloaded what the government says were up to 1.7 million secret documents about U.S. intelligence-gathering and partnerships with allies, according to U.S. officials, including some that revealed the extent of the data collection.

Among the revelations in the documents was the NSA’s bulk collection of phone and Internet metadata from U.S. users, spying on personal communications of foreign leaders, and the NSA’s ability to tap undersea fiber-optic cables and siphon data.

Follow NBC News Investigations on Twitter and Facebook.

Obama appointed a review board that criticized the domestic data collection. In March the president recommended ending bulk domestic metadata collection, and last week the House passed a bill to end it.

Snowden documents also were the basis for three exclusive NBC News digital reports, on Jan. 27, Feb. 4 and Feb. 7, as well as a report on Nightly News, documenting operations by British cyber spies to monitor YouTube and other social media services and to use an array of “dirty tricks” against nations, hackers, terror groups, suspected criminals and arms dealers.