TOKYO - The US-Pakistani relationship remains challenging for both despite the reopening of Pakistani land routes to resupply US troops in Afghanistan, US Secretary of State Hillary Clinton said on Sunday.

Clinton last week apologized for a November NATO air strike that killed 24 Pakistani soldiers and Islamabad responded by reopening the overland supply routes that are crucial to the US-led war in Afghanistan.

The supply route deal removed one headache, but ties are likely to remain strained by other differences. These include Pakistan's opposition to US drone strikes aimed at militants on its territory and Washington's allegations that Islamabad condones, or even assists, anti-American militants.

Please LIKE our Facebook page - it makes us stronger