WASHINGTON — President Barack Obama plans to freeze the salaries of his top aides at the White House and appointees across his government. A senior administration official said Tuesday that Obama likely will talk about the freeze when he speaks to Congress on Wednesday. The official spoke on the condition of anonymity to discuss the speech before Obama delivers it. This year's move follows a gesture Obama made last year when he froze salaries of White House aides who make more than $100,000.