A third report from Oxfam, in the form of an open letter to the prime minister, Gordon Brown, warns the situation in Afghanistan could lead to a humanitarian disaster.
The warnings coincided with separate bomb attacks in Helmand province and Kandahar, which killed a total of seven people.
A suicide bomber blew himself up beside people who were praying inside a mosque in the provincial capital of Lashkar Gah, said the province's police chief, Mohammad Hussein Andiwal.
Helmand's deputy governor, Pir Mohammad, was killed in the blast, which killed five other people and wounded 18 others, seven seriously. The mosque's prayer leader was also killed, he said.
Haji Ikramullah, a witness who was on his way to pray at the mosque when the blast shook the ground, said he saw dead bodies inside and wounded people crying in pain.
The blast happened hours after another suicide bomber in a car targeted an Afghan army bus in Kabul, killing one civilian and wounding four other people, officials said.
"Urgent changes are required now to prevent Afghanistan from becoming a failing or failed state," Reuters reported the study, by General James L Jones for the Atlantic Council of the United States, as saying.
"If Afghanistan fails, the possible strategic consequences will worsen regional instability, do great harm to the fight against Jihadist and religious extremism, and put in grave jeopardy Nato's future as a credible, cohesive and relevant military alliance."
Another stark forecast comes from the Afghanistan Study Group, created by the Center for the Study of the Presidency, which is also responsible for the Iraq Study Group. The group is co-chaired by Jones with Thomas Pickering, a former US ambassador to Russia and other countries.
The report says the progress gained from six years of international efforts in Afghanistan "is under serious threat from resurgent violence, weakening international resolve, mounting regional challenges and a growing lack of confidence on the part of the Afghan people about the future direction of their country".
The strategy for Afghanistan is clearly lacking a winning formula as there are "too few military forces and insufficient economic aid", it said. But beyond that, the report criticised a centralised power base in Kabul, which left the rest of the country open to the destabilising forces of the Taliban, ousted in 2001, and al-Qaida, as well as the strong opium industry and "stark" poverty suffered by the majority of Afghans.
Contributing to the failure is a diffuse focus, lost in efforts to stabilise Iraq. The study group suggests the US should "decouple" Iraq and Afghanistan, clearly delineating funding streams for each country.
Other recommendations include increasing Nato force levels and military equipment to the country, establishing a special US envoy to Afghanistan, and the development of a 5-year strategy for regional stabilisation with partner nations.
The US defence secretary, Robert Gates, had a more upbeat assessment. "I would say the security situation is good. We want to make sure it gets better, and I think there's still a need to coordinate civil reconstruction, the economic development side of it."
In the UK, the international development charity, Oxfam, urged Gordon Brown to change course in Afghanistan, while lamenting that many of the targets set for the country over two years have not been met.
The charity believes that if the rife poverty is addressed, especially through agricultural development, the insurgency and the opium trade would be less able to take hold. Eradication programmes aimed at opium production only encourage farmers to turn to the insurgents, the letter warns. "Too much aid is slow, wasteful, ineffective or uncoordinated," it says. "What is needed is greater coordination to achieve aid effectiveness."
© 2008 The Guardian