ISLAMABAD -- Pakistan arrested an "important" French al-Qaida leader on the Pakistan-Iran border, a Pakistani intelligence official told NBC News on Wednesday, amid criticism from the United States that the country is not doing enough to fight militancy.

The official told NBC that Naamen Meziche, a French national of Algerian origin, was a "most-wanted" figure in the terrorist network. 

Meziche is believed to have links with militant groups in Europe and Reuters cited media reports as saying he may have played a role in the Sept. 11, 2001 attacks.

"At this moment, he is in custody of ISI (Inter-Services Intelligence agency) and is being interrogated," the Pakistani official, who spoke on condition of anonymity because he was not authorized to speak to the media, told NBC.

There was no immediate confirmation from French authorities.

Meziche reportedly worked closely with another al-Qaida leader, Younis al-Mauritani, who was responsible for international operations.

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Mauritani was captured by Pakistani authorities in September last year.

Pakistan arrests 3 in 'another fatal blow' to al-Qaida

Pakistan officials told Reuters that Meziche was the ringleader of a group of 11 people who left Germany in 2009 to fight U.S.-led forces in Afghanistan, according to Reuters. They did not specify the time or location of his capture.

U.S. Defense Secretary Leon Panetta said during a trip to Kabul that stabilization efforts in Afghanistan would remain difficult as long as militants had safe havens in neighboring Pakistan, and that Washington was "reaching the limits" of its patience with Islamabad.

Panetta: US patience with Pakistan 'reaching the limits'

U.S. officials often describe Pakistan as an unreliable partner in the war on militancy and demand tougher action against militant groups, especially those based in Pakistan's volatile tribal regions near the border with Afghanistan.

Pakistan says it will not allow any militant safe havens inside its territory, and that it will pursue its own strategy against militant groups.

NBC News' Fakhar ur Rehman in Islamabad and Reuters contributed to this report.

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