WASHINGTON, Feb 7 (Reuters) - Republican U.S. Senator Jeff Sessions on Thursday warned that President Barack Obama's nominee for Treasury secretary could face a tough time winning confirmation if the White House did not clear up a dispute over the Medicare health program. Jack Lew, Obama's former chief of staff and budget director, is due to testify on Wednesday before a Senate panel that is vetting him for the administration's top economic job. Lew would succeed Timothy Geithner who left office last month.

New US Secretary of State John Kerry will hold his first bilateral talks Friday, as he welcomes his Canadian counterpart John Baird to the State Department. He will also meet with a delegation sent to the United States to represent South Korean president-elect Park Geun-Hye, State Department spokeswoman Victoria Nuland told journalists on Thursday. Among the issues likely to be discussed between Kerry and Baird is the controversial $7 billion Canada-to-Texas Keystone XL oil pipeline, which is still awaiting a green light from the State Department.

WASHINGTON, Feb 6 (Reuters) - Timothy Geithner, who played a lead role battling the global financial crisis both at the U.S. Treasury and New York Federal Reserve, is planning to write a book on the U.S. response, a spokeswoman said on Wednesday. Geithner, who was the longest-serving member of President Barack Obama's economic team when he stepped down as secretary of the Treasury last month, is credited with helping to calm the financial storm that swept through Wall Street in 2007-2009.

US officials said tightened security at the American embassy in Ankara had helped save lives Friday when a bomber wearing a suicide vest attacked a checkpoint killing a Turkish guard. A Turkish woman journalist has been seriously hurt and two local security guards were shaken up in the attack. "One of our direct-hire local guards was killed. We offer our deepest condolences to his family," State Department spokeswoman Victoria Nuland said. The bomber had struck the first checkpoint on the embassy perimeter.