Former president Bill Clinton addresses students in Nairobi on Saturday. He and daughter Chelsea are on a nine-day tour of Clinton Foundation projects in Africa. (John Muchucha/AFP/Getty Images)

Former president Bill Clinton veered into the orbit of his wife’s presidential race Monday — and caused some problems for her in the process.

In an interview with NBC News, a sometimes defensive Clinton said that his family and its foundation have never done anything “knowingly inappropriate” when accepting donations from foreign governments.

He also said he would continue to deliver speeches for which he is paid six figures during his wife’s presidential campaign because “I gotta pay our bills.” Clinton asserted that he had “taken almost no capital gains” over the past 15 years — a claim that does not jibe with public tax returns.

These and other remarks during the interview with NBC’s Cynthia McFadden raised concerns among Clinton associates from New York to Little Rock, who fear that the former president did his wife no favors with the performance. At some points in the interview, he came off sounding churlish and angry, while his remarks on the family’s finances risked making the Clintons seem out of touch, said these friends, who requested anonymity in order to speak candidly.

In a statement Monday, the Republican National Committee said Clinton provided “deceptive responses” to questions about the foundation.

Former president Bill Clinton and Environment cabinet secretary Judi Wakhungu listen to students of Farasi Lane primary school on Friday in Nairobi. Bill Clinton is in Kenya with his daughter Chelsea on a nine-day tour of Clinton Foundation projects. (Njue Murimi/AFP/Getty Images)

When asked whether the Bill, Hillary and Chelsea Clinton Foundation created perception problems by accepting large sums from foreign companies and governments, Clinton suggested his family was the victim of a double standard. “People should draw their own conclusions. I’m not in politics,” he said. “All I’m saying is the idea that there’s one set of rules for us and another set for everybody else is true.”

He added later, “There has been a very deliberate attempt to take the foundation down.”

Clinton said that no entity gave the foundation money to try to influence his wife while she served as secretary of state. “There is no doubt in my mind that we have never done anything knowingly inappropriate in terms of taking money to influence any kind of American government policy,” he said. “That just hasn’t happened.”

He said his wife has told him, “No one has ever tried to influence me by helping you.”

The foundation’s finances, and particularly its practice of accepting donations from foreign governments, have drawn considerable scrutiny in recent weeks from The Washington Post and other news organizations and in a new book, “Clinton Cash.”

With Hillary Rodham Clinton beginning her campaign for the 2016 Democratic presidential nomination, the foundation has become fodder for attacks from her opponents, both Democratic and Republican. The Clinton Foundation recently bowed to pressure and announced it would accept foreign donations from only six Western nations and increase transparency by disclosing its donors four times a year instead of annually.

Bill Clinton spoke with NBC from Kenya during his and daughter Chelsea’s annual tour of Africa to visit Clinton Foundation projects that focus on such issues as climate change, public health, conservation, economic growth and empowering women and girls.

“I don’t think there’s anything sinister in trying to get wealthy people in countries that are seriously involved in development to spend their money wisely in a way that helps poor people and lifts them up,” Clinton said.

But he left open the possibility that he would step down from the foundation if his wife is elected president. “I might if I were asked to do something in the public interest that I had an obligation to do,” Clinton told NBC. “Or I might take less of an executive role. But we’ll cross that bridge when we come to it.”

Clinton has earned more than $100 million in speaking fees since leaving the White House, much of it from foreign entities. Asked about his paid speeches, some of which come with a fee of $500,000 or higher, Clinton said, “People like to hear me speak.”

Clinton said it was “laughable” for people to assume that Hillary Clinton couldn’t “relate to the currents of middle-class America because now we have money.”

“I’m grateful for our success,” he said. “But let me remind you: When we moved into the White House, we had the lowest net worth of any family since Harry Truman.”

Tom Hamburger contributed to this report.