(CNN) -- British Prime Minister David Cameron made a surprise visit to the troops in Afghanistan Thursday, a day after he announced a significant drawdown of UK forces there.
"Thank you for what you've done. You make our country proud," Cameron told the troops, according to the official Twitter account for his office at No. 10 Downing Street.
Cameron said Wednesday that UK troop numbers will decrease to about 5,200 by the end of 2013. The country currently has around 9,500 military personnel in Afghanistan, 500 of which will be leaving by the end of this year.
The accelerated withdrawal is due to progress in the southern province of Helmand, where Afghan forces are now taking a lead security role, British officials say.
"We came to Afghanistan to help this country stop being a haven of terror, but we've always wanted this country to be able to police itself, with its own army and its own police force," Cameron said during his visit. "We're successfully training them up so we're able to bring our troops back home."
Cameron said the withdrawal is "based on success, not based on failure."
France pulled its last combat units from Afghanistan over the weekend. About 1,500 French troops will remain the country through next year to remove equipment and help train Afghan forces, a French Defense Ministry spokesman said.
Britain is the second-largest contributor of troops to the NATO-led International Security Assistance Force, with the majority of its personnel operating in Helmand.
Since Operation Enduring Freedom began in 2001, Britain has lost 438 troops, the highest of any coalition member behind the United States.
The United States, whose troops make up the bulk of the force, has lost 2,162 troops in the NATO mission. Some 68,000 U.S. troops remain in Afghanistan.
Coalition forces are working to get Afghan security forces ready to take charge of security after the NATO mission in Afghanistan concludes at the end of 2014.
CNN's Laura Smith-Spark contributed to this report.