Kabul, Afghanistan (CNN) -- U.S. Vice President Joe Biden arrived Monday night in Kabul on an unannounced visit to meet with top U.S. and Afghan personnel ahead of July's planned start of the withdrawal of U.S. troops from the country, a White House official said.
Biden, whose plane landed at Kabul International Airport at 7:24 p.m., was met on the tarmac by U.S. Ambassador Karl Eikenberry, Gen. David Petraeus and three Afghan officials, including First Vice President Marshal Mohammad Qasim Fahim.
Biden, Petraeus and Eikenberry then flew in a helicopter to the U.S. Embassy, a 15-minute trip by air followed by a short motorcade, a pool reporter said.
There, the men met so that Biden could get "an update from them on the situation on the ground," a White House official said.
"The primary purpose of the trip is to assess progress toward the transition to Afghan-led security beginning in 2011, and to demonstrate our commitment to a long-term partnership with Afghanistan," a White House official said.
Biden was also scheduled to meet with Afghan President Hamid Karzai, U.S. service members and civilian personnel, the pool reporter said.
The White House official said Biden's arrival was a surprise because of security concerns, although Karzai was told about it last week. It is Biden's first visit here as vice president.
There are 97,000 U.S. troops in Afghanistan.