CHAMAN, Pakistan — Trucks carrying NATO supplies will resume their routes through Pakistan to Afghanistan on Thursday after Islamabad's agreement to end its seven-month blockade, security officials said.

Implementation of the supply-line agreement should help patch up the U.S.-Pakistan relationship, which is crucial for American efforts to stabilize Afghanistan, but the two continue to have serious differences.

U.S. officials had expected the trucks to begin crossing into Afghanistan on Wednesday, but bureaucratic delays held that up.

Pakistan agreed to reopen the supply line Tuesday after the U.S. said it was sorry for American airstrikes that killed 24 Pakistani soldiers in November. The attack prompted Pakistan to close the route and severely damaged already strained relations between the two countries.

On Wednesday, Pakistan's Cabinet endorsed the decision to reopen the route, which was made by senior civilian and military officials.

Pakistan's plan calls for four trucks to enter Afghanistan on Wednesday through the Chaman crossing in southwestern Baluchistan province, according to a Pakistani security document obtained by The Associated Press. Chaman is one of two crossings used to ship NATO supplies to Afghanistan.

One hundred trucks were also set to begin traveling from the southern port city of Karachi to Chaman and Torkham, the site of the other crossing in the northwest Khyber tribal area, according to the document.

The reopening could save the U.S. hundreds of millions of dollars, since Pakistan's blockade forced Washington, D.C., to rely more heavily on a longer, costlier route that leads into Afghanistan through Central Asia.

Pakistan is also expected to gain financially, since the U.S. intends to free up $1.1 billion in military aid that has been frozen for the past year.

The deal carries risks for both governments.

Pakistan is likely to face a domestic backlash, given rampant anti-American sentiment in the country and the government's failure to force the U.S. to stop drone attacks targeting militants and accede to other demands made by parliament.

The Pakistani Taliban vowed to attack trucks carrying NATO supplies once they start moving, calling the government a slave to the U.S.

Anger at Pakistan is high in the U.S. because of the country's alleged support for militants fighting U.S. troops in Afghanistan.

President Obama risks exposing himself to criticism from Republicans, including presidential challenger Mitt Romney. He contends the administration is too quick to apologize in foreign-policy matters.

This political risk and the underlying anger led the U.S. to hold off apologizing to Pakistan for months, despite repeated demands from Islamabad. In the end, Secretary of State Hillary Rodham Clinton said the U.S. was "sorry" for the deaths of the Pakistani troops, but didn't offer the "unconditional apology" demanded by the country's parliament.

The most vocal opposition to reopening the NATO supply line has come from a collection of hard-line Islamist religious leaders and politicians known as the Difah-e-Pakistan, or Defense of Pakistan Council.

The group, which many suspect was supported by the Pakistani army to pressure the U.S., plans to launch a protest campaign against the supply route decision, said chairman Maulana Samiul Haq.

"It is an insult to our nation," he said. "The rulers have put national interest at stake just to please America."