The new U.S. and NATO commander in Afghanistan, General Stanley McChrystal, on Wednesday voiced concern about growing instability in the west and the north of the country.
Reuters news agency quoted McChrystal as saying he is worried by the worsening security situation in those areas, as well as by pockets of insurgent strength in other parts of the country.
McChrystal said more security forces, especially Afghan troops and police, are needed, as well as increased Afghan government support for efforts to win over the local population.
In Washington, the Pentagon spokesman said any move to further increase the size of the Afghan security force will require an international commitment to provide trainers and funding.
Geoff Morrell said the U.S. is already spending more than $7 billion a year to recruit, train and equip Afghan soldiers.
Morrell said a decision about whether to further increase the size of the Afghan army will not be made until after General McChrystal provides his 60-day assessment next month.
Also Wednesday, the U.N. Security Council hailed Afghan-led preparations for national elections scheduled for August 20, and called on all Afghans to take part in a historic opportunity to make their voices heard.
A Council statement stressed how important it is that the balloting be "free, fair, transparent, credible, secure and inclusive."
The Security Council also praised the European Union, the Organization for Security and Cooperation in Europe and other international organizations for their decision to send electoral observers to Afghanistan.
It urged Kabul to intensify efforts in addressing issues in the areas of security and governance, as well as the rule of law and human rights.
Some information for this report was provided by AP and Reuters.