Pakistani officials say Islamabad's demand for higher tariffs on NATO supplies are not blocking talks on reopening NATO supply routes to Afghanistan.

Pakistani Foreign Minister Hina Rabbani Khar told reporters Wednesday that suggestions Pakistan is involved in what she called a “price-gouging debate right now” are “wrong and must be dispersed [dispelled] as soon as possible.”

Pakistan closed the NATO supply lines in November after a U.S. airstrike mistakenly killed 24 Pakistani troops near the Afghan border. Before the closure, U.S. officials said NATO paid on average $250 per container, but since then, the Pakistani government has requested ten times more, saying the new prices are to offset damage to their roadways from the convoys. So far, the two countries have not agreed on any new tariffs.

The United States also has refused Pakistani demands to apologize for the airstrike incident and Islamabad's insistence on stopping unmanned drone strikes in its territory. Washington sees the drones as one of its most effective ways to target Taliban and al-Qaida-linked militants in Pakistan's semi-autonomous northwest. Earlier Wednesday, the latest U.S. drone strike killed four suspected militants near the Afghan border.

Despite the impasse, U.S. Ambassador Cameron Munter said Wednesday that both countries still are working on the issue and that he believes both sides are “anxious” to see it resolved.

Earlier in the day, NATO chief Anders Fogh Rasmussen said he hoped supply routes through Pakistan into neighboring Afghanistan will be reopened soon.

He also stressed the importance of agreements he announced last week for NATO to withdraw equipment through Kazakhstan, Kyrgyzstan and Uzbekistan as the Afghan war winds down.

With the Pakistani borders closed to NATO supplies, the international coalition has turned to Central Asian nations for more expensive and longer land routes.