President Barack Obama on Wednesday reaffirmed U.S. commitment to Afghanistan's security and prosperity, saying the country is still facing severe challenges although some progress have been made.

U.S. President Barack Obama (R) and visiting Afghan President Hamid Karzai attend a joint press conference after their meeting at the East Room of the White House in Washington D.C., capital of the United States, May 12, 2010. [Zhang Jun/Xinhua]

"I have reaffirmed the commitment of the United States to an Afghanistan that is stable, strong and prosperous," Obama told reporters at the joint press conference with Afghan President Hamid Karzai in the White House.

According to Obama, Karzai's visit is an opportunity for both sides to assess the progress of U.S. strategy in Afghanistan and to advance the strong partnership between the two countries which is based on mutual interest and respect.

After 30 years of war, Afghanistan still faces daily challenges in delivering basic services and security to its people while confronting a brutal insurgency," said Obama.

He reiterated that U.S. strategy in Afghanistan is centered at disrupting, dismantling and defeating al-Qaida and its extremist allies in Afghanistan and Pakistan and to prevent its capacity to threaten America and U.S. allies in the future.

He promised that the United States will continue to work with our Afghan and international partners to do everything in their power to avoid actions that harm the Afghan people during the implementation of the strategy.

According to Obama, during the White House meeting, he convinced Karzai that Washington supports the efforts the Afghan government has made on combating corruption, taking good governance, and negotiating with the Taliban.

"The United States supports the efforts of the Afghan government to open the door to Taliban who cut their ties to al- Qaida, abandon violence, and accept the Afghan constitution, including respect for human rights," said the president.

President Karzai, who is paying a four-day visit to the United States, has met with Secretary of State Hillary Rodham Clinton, Secretary of Defense Robert Gates and other senior U.S. officials, as well as top military officers in Washington.

After months of review, the Obama administration renewed its strategy for Afghanistan last December by sending 30,000 additional troops to the country in a decisive war against al- Qaida network and extremists.

The U.S. army forces stationed in Afghanistan would surge to about 100,000 troops.

President Obama has urged the Karzai-led government to combat corruption and take good governance in order that a transfer of responsibility could be promoted and that the United States could begin to withdraw its troops since July of 2011.

He told reporters that the two governments have deepened cooperation on training Afghan security forces so that they can begin to take the lead in security next year. "We're working with the Afghan government and our allies on a broader framework to guide the transition of responsibility for security, development and governance in Afghan provinces."

Echoing Obama's remarks, President Karzai said that through the partnership with the United States, the progress of the past years the Afghanistan people have made are "numerous and great," adding that the country will "take the right steps in bringing a better government to Afghanistan for the benefit of the Afghan people."