President Barack Obama arrived in the Portuguese capital on Friday for two days of meetings that will put his Afghanistan war strategy in the spotlight.
Obama will meet with Portugal's President and Prime Minister before attending the opening session of the NATO summit.
NATO countries are expected to set a goal of giving Afghans control of their security by the end of 2014. The alliance will also pledge a longer-term commitment to Afghanistan focused on training and development.
On Saturday, Obama will meet with Afghan President Hamid Karzai. Obama also will participate in a brief summit with European Union leaders before departing for Washington on late Saturday.