Vermont Rep. Peter Welch says he remains skeptical of U.S. strategy in Afghanistan after spending several days in the region and meeting with American officials and troops.

Welch, a Democrat taking part in the five-person congressional trip, spent about two days in Afghanistan and a day-and-a-half in Pakistan reviewing the military and political progress in the ongoing conflict. Speaking with reporters by telephone Monday from Tbilisi, Georgia, Welch offered a dim view of the conditions on the ground after meetings with U.S.military commander Gen.David Petraeusand Ambassador to Afghanistan Karl Eikenberry.

Welch cited some security improvements since his last visit, before President Barack Obama ordered 30,000 additional troops to the country. "There are many parts of Afghanistan where it's safe and calm," he said.

But rampant corruption, a problem Welch lamented during his trip to the region last November, has not been curtailed. "The recurring theme was the corruption that exists in Afghan society is an enormous impediment," he said of his meetings with U.S. officials.

Additionally, "petty corruption" by Afghan police has the potential to undermine U.S.-backed efforts, Welch said. Afghan President Hamid Karzai must take responsibility and rein in corrupt government and military officials, as well as police, Welch said.

Petraeus, meanwhile, who replaced Gen. Stanley McChrystal, has the "full confidence of troops," according to Welch. But the task in Afghanistan is "much more challenging in many ways than what he did in Iraq," overseeing former President George W. Bush's "surge" strategy, Welch said.

Petraeus' counterinsurgency strategy requires support from the Afghan people, and a confidence by the population in governmental institutions, Welch said, neither of which are guaranteed. "There are thousands of villages in Afghanistan where the loyalties of the people is up for grabs," he said.

Success in Afghanistan is also contingent on cooperation from Pakistan. But it's unclear whether Pakistan is doing everything it can to quell the Afghan Taliban and other insurgents, Welch said. The Haqqani network, an independent insurgent group closely aligned with the Taliban, appears to have sanctuary in Pakistan, he said, despite assurances from Pakistani military officials pledging full support.

"The Pakistani military has been saying that for years, but not really," Welch said. "The bottom line is, if they tolerate the Afghan Taliban having a safe haven that's a big threat to our troops."

Elements in both Afghanistan and Pakistan are "a real threat to America," Welch said. "It's very important for all of us to acknowledge ... there are people who want to hurt us," he said.

But Welch, who voted against sending additional troops to the conflict, said he would prefer a solution focusing on special operations "where we use intelligence and we take military action where appropriate."

The counterinsurgency strategy will be difficult with "a dispersed and decentralized threat," and may not be financially sustainable, Welch said. Nation building is an "extraordinarily labor-intensive process," he said.

"The question is whether this is a policy that we can sustain," he said. "I continue to be skeptical. Gen. Petraeus' approach, counterinsurgency, is explicitly about building the local capacity ... to have a functioning society."

The congressional delegation began its trip in Beirut, meeting with Lebanon's prime minister and defense minister, before traveling to Afghanistan and Pakistan. The group was planning to depart Georgia to return to the U.S. today.

Welch also met at Bagram Air Base with some of the 1,500 or so members of the Vermont National Guard serving in Afghanistan. He said his goal was "to make it clear to our soldiers ... that Vermonters respect the service they're providing to the country."

The troops are working hard and miss their families, Welch said, and they have an impeccable reputation among military leaders.

"It became very evident that the Vermont contingent of soldiers has a high reputation among the highest-ranking soldiers within the military," he said. "It made me quite proud because I'm sitting there with four other members of Congress and the only group mentioned was Vermonters."