(CNN) - Following weeks of questions over Mitt Romney's personal wealth, the presumptive GOP nominee said Thursday that criticism of the nation's wealthy, including his family, would lead to economic demise.
"There are people who are trying to attack success and are trying to attack our success; that's not going to be successful," Romney said in an interview to air Thursday on CNN's "Piers Morgan Tonight." "When you attack success you have less of it, and that's what we've seen in our economy over the last few years."
- Follow the Ticker on Twitter: @PoliticalTicker
The 2012 presidential campaign has centered on debate over Romney's wealth this summer, with President Barack Obama's team raising concerns about the Republican's decision to hold offshore investments and calling on Romney to release tax documents to answer any lingering queries about his financial portfolio.
The White House hopeful has firmly stated he would not release anything further than the two years worth of tax documents that he has already released and annual financial disclosure forms separately required by federal election law.
Romney, whose wealth is worth up to $256 million, has also been railed against over his tenure at the private equity firm he co-founded, Bain Capital. Democrats argue he has been misleading about when exactly he left his position as CEO at the company, saying he stayed on three years longer than he's previously admitted-a time window, Democrats say, in which he would have overseen a period in which the company is now being criticized for encouraging the practice of outsourcing.
Along with defending his personal wealth, Romney and Republicans have strongly stood against Obama's recent proposal to raise taxes on households making more than $250,000 per year, arguing such a move would have a negative impact on the economy and discourage growth.
"Dividing America based on who has money and who hasn't – who is successful and who is less successful… That is not the American way," Romney said.
Obama, defending his tax proposal, has frequently said his policies are not aimed as an attack on the wealthy.
"This has nothing to do with me wanting to punish success. We love folks getting rich. I do want to make sure that everybody else gets that chance as well." Obama said at a campaign stop in Iowa earlier this month. "For us to give a trillion dollars worth of tax breaks to folks who don't need it and aren't even asking for it, that doesn't make sense."
Romney made his comments during a sit-down interview in London, with his wife Ann by his side. The former Massachusetts governor, who headed the 2002 Winter Olympic Games in Salt Lake City, is in town to attend Friday's opening ceremony for this year's Olympic Games. The stop in London marks the first leg of a three-country trip, which also takes him to Israel and Poland over the next week.
Romney also pointed to Florida Sen. Marco Rubio, who Romney has admitted his campaign was considering–among others–for his running mate, and quoted a statement the freshman senator frequently makes about class warfare rhetoric.
"I heard Marco Rubio the other day, he said, 'You know, we were poor living in Miami, we saw these big homes across town…my parents never said to us, gee why don't those people give to us some of what they have. They said instead, aren't we lucky to live in a country where with education and hard work we might be able to achieve that ourselves'."
Democrats have especially hammered Romney over his former firm, Bain Capital. Priorities USA Action, a pro-Obama super PAC, has released multiple commercials this summer highlighting companies that failed–and their subsequent job losses–after being invested in by Bain. While the company has said most of its companies have succeeded, Romney gave rare insight on Thursday into some of the firm's failures.
"It killed us if something was not successful. If a business we started, for instance, couldn't make it-and there were several like that-but there were several that took off in ways that we never would have imagined. There are a number of businesses that were existing businesses we wanted to make better. Most of them we did make better. Those that we didn't, we felt terrible about," he said.
In the wide-ranging interview, Romney also discussed his position on gun rights in the wake of the Colorado movie theater massacre that left 12 dead and dozens wounded.
The former governor has said in recent days he sees no need for new gun legislation, arguing that people who want to do harm will find a way to get around any further laws.
"The real point has to relate to individuals that are deranged and distressed and to find them, to help them and to keep them from carrying out terrible acts," he said. "Timothy McVeigh, how many people did he kill? With fertilizer? With products that can be purchased legally anywhere in the world, he was able to carry out vast mayhem." '
He added: "Somehow thinking that laws against the instruments of violence will make violence go away, I think is misguided."
Obama on Wednesday made headlines by making his strongest comments yet as president about gun violence. While he called for change, he did not specifically outline any proposals for new gun legislation.
"A lot of gun owners would agree that AK-47s belong in the hands of soldiers, not in the hands of criminals," Obama said at the National Urban League convention in New Orleans. "That they belong on the battlefield of war, not on the streets of our cities."
The president emphasized a need for background checks and the prevention of "mentally unbalanced" individuals from obtaining guns. He faulted opposition in Congress for lack of progress made in reducing violence.
"These steps shouldn't controversial. They should be common sense," Obama said.
- Watch the full interview at 9 p.m. ET on CNN's "Piers Morgan Tonight."
Watch Piers Morgan Live weeknights 9 p.m. ET. For the latest from Piers Morgan click here.