PORTSMOUTH — To President Donald Trump's 87 percent approval rating among the Republican Party, former Massachusetts Gov. Bill Weld says, "My view is he is not doing anything for those people except screaming and trying to make everyone upset and believe there is someone on the ladder below them trying to take their place."

"The worst kind of politics," he added.

Weld, a self-proclaimed economic conservative who values inclusivity, the environment and individual freedoms, is the only Republican candidate so far to seriously launch an exploration into challenging Trump in the 2020 primary. During an editorial board meeting with Seacoast Media Group this past week, Weld said he will make a formal decision in April. He was accompanied by former New Hampshire GOP chairwoman Jennifer Horn.

Weld served as the 68th governor of Massachusetts from 1991 to 1997, and was the Libertarian Party's nominee for vice president in the 2016 election alongside former New Mexico Gov. Gary Johnson.

Weld was legal counsel to the U.S. House Committee on the Judiciary, before becoming the U.S. Attorney for the District of Massachusetts and, later, the U.S. assistant attorney general for the Criminal Division. During his time as an attorney, he made public corruption cases his No. 1 priority, he said.

While Weld is fiscally conservative, he said socially he falls closer to the liberal side. "I was pro-choice when that was a minority view, early pro-gay and lesbian rights, by myself for 20 years on that one," he said. "I was perceived as a distinct social liberal, but ranked the most fiscally conservative governor in the United States."

During his time as governor, Weld said he took pride in his office's outreach, by creating coalitions for Hispanics and African Americans, for example. "Trying to make everyone feel included, the opposite of Donald J. Trump," he said.

Weld said his differences with Trump "go deep."

"I’ve been an ardent environmentalist my whole life, and clean air and clean water are very important to me," he said, noting he brought a lawsuit to clean up Boston Harbor in the 1980s. "If I were to be successful in getting the Oval Office, I would put us back in the Paris Climate Accord on day 1. Probably be very aggressive about environmental enforcement."

Weld also distinguishes himself from Trump with budgeting style. Trump has not addressed the nation's rapidly growing debt and deficit, he said, and is instead adding to it. Weld said he would "zero base" the federal budget, where budgeting is based on outcomes from the previous year.

"That’s how you get to diminish the budget and the spending and not have the deficit," he said, adding, overall, he wants to cut both spending and taxes.

Weld has already spent a significant amount of time in New Hampshire, where he said so far he's been well-received. If he wins the First-In-The-Nation primary, though facing an uphill battle, he said, "I think it is possible for me to win the whole thing."

"In terms of practical politics, one of my charges here is to enlarge the electorate that’s going to participate in the Republican primary," he said. "I’d like to change the shape of the electorate, too. My campaign says, and I truly believe, it’s in the interest of the United States to have as many people as possible participate in the election."

Asked about his position on gun laws, Weld said he generally took the side of gun owners against police chiefs in Massachusetts because the law empowered the police chief to say anybody could not own a gun "and I was familiar with cases where the police chief just didn't like the guy." He also raised the concept of self defense, and said "some of the greatest massacres in history" around the world came after political leadership outlawed private possession of firearms. Weld did express an openness to measures that would keep guns out of the hands of those who were proven a danger to themselves or others due to a mental illness.

After his experience in the 2016 election, Weld said he's become "more of a constitutionalist," and actually reads the document every few weeks.

"I hope it’s OK to be a Republican and be in favor of clean air and clean water," he said. "I hope it's OK to want to involve everybody and unleash everybody’s energy."