New Delhi, Sept. 25 -- Barack Obama has acknowledged that his marriage to Michelle Obama went through a difficult period following his two terms as President of the United States.

Speaking at the O2 Arena in London during a conversation with historian David Olusoga, 64-year-old former president Barack Obama joked that he had been "digging [himself] out of the hole" he found himself in with his wife after leaving office. "Now I'm at about level ground," he told the audience.

The admission echoes remarks Obama made earlier this year. In April, he told Hamilton College President Steven Tepper that he had been "in a deep deficit" with Michelle, now 61, after the demands of his presidency took their toll. "I have been trying to dig myself ou...