WASHINGTON (AP) — President Barack Obama announced new oversight measures for recently revealed domestic and foreign surveillance programs, saying he is confident they are "not being abused" but that they must be more transparent.

He gave no indication on Friday the government would end the massive collection of information about telephone calls and emails of Americans and those abroad.

Recent leaks about the surveillance programs have led to the strongest challenge yet to the vast powers Congress granted the president after the 2001 terror attacks on the U.S.

In his first news conference since April, Obama also explained this week's decision to cancel a summit next month with Russian leader Vladimir Putin. He said he's had only "mixed" success in resetting the tense relationship between the two countries.

Russia's recent decision to grant asylum to National Security Agency leaker Edward Snowden was not the only reason for canceling the meeting, Obama said. Snowden, a former analyst, revealed details of the secret surveillance programs, and the U.S. wants him to come home to face espionage charges.

Obama encouraged Putin to "think forward instead of backward" on a long list of issues, including Syria's civil war and human rights, and he said his administration was pausing to determine how best to improve the countries' difficult relationship.

In wide-ranging comments lasting nearly an hour, Obama also said it would not be appropriate to boycott the upcoming Winter Olympics in Sochi over Russia's new anti-gay law.

And the president declined to confirm a series of drone strikes recently reported carried out in Yemen to deter a suspected terrorist plot.

But Obama largely focused on the surveillance programs in an effort to calm fears and anger about privacy rights, both in the U.S. and overseas.

The spying program has been kept secret for years, and the administration falsely denied it existed.

The bulk collection of phone records was authorized under the USA Patriot Act, which Congress hurriedly passed after the 2001 terrorist attacks.

The NSA says phone records are the only things it collects in bulk under that law. But officials have left open the possibility that it could create similar databases of people's credit card transactions, hotel records and Internet searches.

The modest changes Obama announced Friday include the formation of an outside advisory panel to review U.S. surveillance powers, assigning a privacy officer at the NSA, and the creation of an independent attorney to argue against the government before the nation's surveillance court.

All those new positions would carry out most of their duties in secret.

Obama has found Congress surprisingly hostile to the surveillance programs since they were made public, especially from an unusual coalition of libertarian-leaning conservatives and liberal Democrats.

The administration says it only looks at the phone records when investigating suspected terrorists. But testimony before Congress revealed how easy it is for Americans with no connection to terrorism to unwittingly have their calling patterns analyzed by the government.

When the NSA identifies a suspect, analysts can look not just at the suspect's phone records but also the records of everyone the suspect calls, everyone who calls those people and everyone who calls those people.

Obama spoke a day before he leaves for his annual vacation. Congress is already on holiday.