NEW YORK - Admiral Michael Mullen late Wednesday afternoon confirmed the existence of a secret memo alleged to have been sent by President Asif Ali Zardari that the top US military officer had earlier not recollected receiving, a dispatch posted on Foreign Policy magazine said. The confirmation led Pakistan's Ambassador to the United States Husain Haqqani, whose became embroiled in the raging controversy over the memo, to offer his resignation to President Zardari, The FP dispatch said, "Haqqani, who has long been a key link between the civilian government in Pakistan and the Obama administration, has also been battling for years with the Pakistani military and the Inter-Services Intelligence (ISI), Pakistan's chief spy agency -- two organizations whose influence in Washington he has fought to weaken. That battle came to the fore of Pakistani politics this month due to the growing scandal known in Pakistan as 'memo-gate,' which relates to a secret backchannel memo that was allegedly conveyed from Zardari to Mullen, through Pakistani-American businessman Mansoor Ijaz". Ijaz alleged in an Oct. 10 op-ed in the Financial Times that on May 10, in the wake of Osama bin Laden's killing in Abbottabad, Zardari had offered to replace Pakistan's powerful military and intelligence leadership and cut ties with militant groups. Ijaz said he was directed to craft the memo by a senior Pakistani official close to Zardari. Ijaz has implied -- and the Pakistani press has speculated -- that this official was Haqqani. Last week, The Cable published a report on Mullen's comments about the memo. "Adm. Mullen does not know Mr. Ijaz and has no recollection of receiving any correspondence from him," Mullen's spokesman Captain John Kirby said Nov. 8. "I cannot say definitively that correspondence did not come from him -- the admiral received many missives as chairman from many people every day, some official, some not. But he does not recall one from this individual." Ijaz responded in an article in a Pakistani newspaper, in which he published extensive Blackberry Messenger conversations with the Zardari-linked Pakistani official, allegedly Haqqani. He insisted that the memo did, in fact, exist, and that it was delivered from Ijaz to Mullen through another secret go-between, this one a senior U.S. government official. "There can be no doubt a memorandum was drafted and transmitted to Admiral Mullen with the approval of the highest political level in Pakistan, and that the admiral received it with certainty from a source whom he trusted and who also trusted me," Ijaz wrote. Kirby told The Cable Wednesday that Mullen now acknowledges that the Ijaz memo does exist, that he did receive it -- but that he never paid any attention to it and took no follow up action. "Adm. Mullen had no recollection of the memo and no relationship with Mr. Ijaz. After the original article appeared on Foreign Policy's website, he felt it incumbent upon himself to check his memory. He reached out to others who he believed might have had knowledge of such a memo, and one of them was able to produce a copy of it," Kirby said. "That said, neither the contents of the memo nor the proof of its existence altered or affected in any way the manner in which Adm. Mullen conducted himself in his relationship with Gen. Kayani and the Pakistani government. He did not find it at all credible and took no note of it then or later. Therefore, he addressed it with no one." Pakistani opposition leaders have seized upon the controversy. Meanwhile, the Pakistani military, led by Army Chief of Staff Gen. Ashfaq Parvez Kayani, has been pressuring Zardari to start an inquiry into the memo. In an interview with The Cable late on Wednesday afternoon, Haqqani confirmed that he will travel to Islamabad and has sent a letter to Zardari offering his resignation. "At no point was I asked by you or anyone in the Pakistani government to draft a memo and at no point did I draft or deliver such a memo," Haqqani said that he had written in his letter to Zardari. "I've been consistently vilified as being against the Pakistani military even though I have only opposed military intervention in political affairs," Haqqani said that he wrote. "It's not easy to operate under the shadow of innuendo and I have not been named by anyone so far, but I am offering to resign in the national interest and leave that to the will of the president." Haqqani declined to comment whether or not he played any role in the controversy surrounding the memo -- for example, discussing it with Ijaz before or after the fact, as the scandal deepened. It's widely rumoured that Haqqani and Ijaz have known each other for many years. The dispatch said, "It's remains unclear whether Zardari had any knowledge of the memo at the time. In Islamabad, some speculate that Zardari may be trying to put an end to the memo-gate controversy by sacrificing Haqqani, but no decision has yet been made on whether or not Haqqani will step down. If he leaves, he will return to private life having played a key role in the U.S.-Pakistan relationship during its most tumultuous period -- a role that is mired in the secrecy and intrigue of Pakistani politics and diplomacy." According to Haqqani, he is the target of a media campaign backed by the supporters of the military's role in politics because he has focused on building ties between the U.S. and Pakistani civilian governments, rather than with the Pakistani military. "Eighty percent of Pakistanis don't want a good relationship with the U.S., and anyone who stands up for the United States can expect to be vilified," he said.