WASHINGTON (Reuters) - The United States said on Thursday it has asked Russia for more time to end the U.S. Agency for International Development's work in the country after Russian authorities gave them until October 1 to close the operation.

State Department spokeswoman Victoria Nuland declined to say how much time the United States wanted to comply with Russia's decision, which analysts regarded as part of the Kremlin's wider crackdown on pro-democracy groups.

Nuland told reporters the United States promised Russia "there will be no new contracting, no new programming, as of October 1, but we have also asked for some time to wind down the mission, to conclude the programs that we have underway."

Russia gave USAID until October 1 to cease operations after two decades and more than $2.6 billion spent to combat disease, protect the environment, strengthen civil society and modernize the economy.

Vladimir Putin, who served eight years as president and a further four years as prime minister, took office in May for a third presidential term after winning nearly two-thirds of the vote in an election monitors say was skewed in his favor.

In a sign of his reluctance to brook dissent, Putin has pushed through new laws to raise fines for protesters, stiffen punishments for defamation and put new controls on foreign-funded campaign groups.

In announcing the decision on Tuesday, the State Department said USAID will continue to promote democracy and civil society despite no longer having an office in Russia. A U.S. government official said that the decision to close down the office would affect 13 U.S. diplomats and 60 local Russian employees.

Nuland said Clinton had written a letter to Russian Foreign Minster Sergei Lavrov "expressing regret that these programs were going to end ... and making clear that we would, as I said, cease new contracting but that we needed a little time."

USAID has a 2012 budget in Russia almost $50 million, more than half of which is spent on human rights and democracy work. About 40 percent of the overall funding goes directly to Russian organizations.

(Reporting by Arshad Mohammed; Editing by Jackie Frank)