The U.S. ambassador to Afghanistan, Ryan Crocker, says Pakistan's absence from the upcoming international conference on Afghanistan would be “unfortunate,” but will not derail Afghan progress or change the outcome of the gathering.

In an interview with VOA Saturday, Crocker said it will be Pakistan's loss if it boycotts the talks on Afghanistan's future, scheduled to begin Monday in Bonn, Germany.

Pakistani officials said repeatedly they would not participate in the Bonn conference, in protest of NATO airstrikes late last month that killed 24 government troops near the Afghan border.

Crocker said that, over the past decade, Afghanistan has gone through many changes, including the toppling of the Taliban government, a significant rise in the life expectancy of Afghans and economic activity. Crocker noted that when he first arrived in the country, 900,000 children were in school and today there are over 8 million school children. Nearly 40 percent are girls. Crocker says he expects more changes in security in the coming years.

The talks are taking place 10 years after the original conference, also in Bonn, in which diplomats appointed a transitional government in Afghanistan. At the upcoming gathering, to be attended by representatives from 85 countries, the international community is expected to renew its long-term commitment to Afghan security, stability and prosperity.

At the conference, world leaders are expected to further discuss the role of the coalition after the 2014 deadline for withdrawal of all foreign combat troops from the war-torn country.