The United States and Pakistan started their third strategic dialogue this year on Wednesday in Washington, during which security, economic, agricultural and other topics will be discussed by the two sides.

The three-day talks are designed to serve as "a venue" to ease tensions in the bilateral relations, Frank Ruggiero, U.S. deputy special representative to Afghanistan and Pakistan, said on Tuesday.

State Department spokesman Phillip Crowley told reporters on Wednesday that the discussion on Wednesday morning has touched on agriculture, communications and other issues. The dialogue is made up by 13 working groups.

In the afternoon, Defense Secretary Robert Gates, Chairman of the Joint Chiefs of Staff Mike Mullen and other senior U.S. military leaders met with Pakistani Army Chief of Staff Ashfaq Parvez Kayani and members of his staff.

The U.S.-Pakistan relations are sometimes marred by U.S. complaints that Pakistan is not doing enough to crack down the Taliban fighters within its territory.

Pakistan has also expressed its frustrations on the slow pace of economic aid and U.S. lack of sympathy for its confrontation with India. It is particularly angered by the recent accidental killings of three Pakistani soldiers by a NATO helicopter gunship, which led to the shut-down of a NATO supply line into Afghanistan.

The dialogue, the third one of its kind this year, underscores the Obama administration's efforts to woo Pakistan, a key player in the war in Afghanistan.

Pentagon Press Secretary Geoff Morrell said on Wednesday that Gates apologized for the "unintentional" attack that killed three Pakistani soldiers and talked about the need to better coordinate operations along the Afghanistan-Pakistan border.

The dialogue, co-chaired by U.S. State Secretary Hillary Clinton and Pakistani Foreign Minister Shah Mahmood Qureshi, is expected to address a multi-year security assistance package for Pakistan.

Reports said the assistance package will involve the sale of U. S. military equipment to Pakistan, which has long been in Pakistan's demand list. The United States hoped that the equipment can strengthen Pakistan's capacity to fight Taliban militants.

The U.S. Congress last year has already approved a five-year, 7.5-billion-dollar nonmilitary aid package.

In return, the United States is expected to continue to pressure Pakistan to step up its efforts to fight Taliban militants in its border.

Crowley said on Wednesday that the United States wants to see greater actions by Pakistan, "particularly focused on North Waziristan."

White House spokesman Robert Gibbs told reporters on Tuesday that during the dialogue the United States will "detail for the Pakistanis what more must be done."