Washington (CNN) -- U.S. officials concede some members of Pakistan's spy service may be encouraging the Taliban to continue fighting U.S. and coalition forces in Afghanistan, but insisted there is no suggestion that the agency's leadership is behind the effort.
The officials were reacting Thursday to a Wall Street Journal story, published a day earlier, that said officers from Pakistan's Inter-Services Intelligence agency are pushing Taliban field commanders to fight against the United States and other NATO troops in Afghanistan.
Pentagon spokesman Col. Dave Lapan told reporters Thursday that "the ISI as an organization does not support terrorism, but whether there are elements within the ISI that are doing things that are not productive, that's what we are discussing."
Lapan said the United States has been talking with the Pakistani Army chief, Gen. Ashfaq Kayani, about the problem.
"The ISI has done a great deal in fighting terrorism," he said, but he added that U.S. officials "also have some concerns with the strategic focus of the ISI."
"Gen Kayani is aware and shares that, and they are working toward making changes. But change happens slowly, over time," Lapan said.
The Defense Department spokesman stressed the United States is not blaming official leaders of the Pakistani spy agency, but the Pentagon's concern is that "elements of the ISI might be interacting with terrorist organizations in ways that aren't consistent with what the government and the military are doing."
A U.S. official who would not speak on the record because of the sensitivity of the U.S.-Pakistani relationship also said there is no indication the leadership of the ISI is trying to direct the Taliban. The official said Pakistan has a patchwork of security agencies, some of which have had ties to extremist groups.
Although it's possible there are some elements within the ISI that are encouraging the Taliban -- "this is Pakistan, you can't rule out anything" -- the official said there is no centrally directed effort by the ISI.
The official added, "We keep our eyes wide open here, because historical relations are hard to break for some people."
A senior Pakistani military official said, "these are baseless reports. There are vested interests behind these allegations."
The Pakistan government and the ISI supported the Taliban when it controlled Afghanistan during the 1990s. The government broke ties with the Taliban after the 9/11 terrorist attacks on the United States.
American officials have consistently indicated there are rogue elements within the ISI that have continued to give support to the Taliban.
The report comes at a time of increasing tension between the United States and Pakistan. The U.S. ambassador to Pakistan, Anne W. Patterson, and the chairman of the Joint Chiefs of Staff, Adm. Mike Mullen, both have issued apologies over the recent killing of Pakistani soldiers by gunfire from a U.S. helicopter on the Afghan border.
Also, a White House report to Congress surfaced Wednesday critical of Pakistan, saying that it is not doing enough to go after Taliban and al Qaeda.
White House spokesman Robert Gibbs said the situation with Pakistan is "very difficult and complicated."
Pakistani leaders will be in Washington later this month to meet with Obama administration officials. Gibbs said the discussions will focus on "fighting insurgents and extremists that we know threatened Pakistan, threatened the stability of Afghanistan, and ultimately threatened the security of our homeland."
CNN's Frederik Pleitgen contributed to this report.