It's time for Egyptian President Hosni Mubarak to "relinquish power," Sen. John McCainJohn Sidney McCainBiden falters in pledge to strengthen US alliances 20 years after 9/11, US foreign policy still struggles for balance What the chaos in Afghanistan can remind us about the importance of protecting democracy at home MORE (R-Ariz.) said shortly after a meeting with President Obama. 

McCain, via Twitter, urged Mubarak to step down amid continued protests of his leadership across Egypt.

McCain, the ranking member of the Senate Armed Services Committee, tweeted:

Regrettably the time has come 4 Pres. Mubarak 2 step down & relinquish power. It’s in the best interest of Egypt, its people & its military.

McCain's public declaration came after a planned one-on-one meeting between him and the president in the Oval Office this afternoon, the first since 2008 for the two rivals from that presidential campaign. 

Mubarak had announced on Tuesday that he would begin the process of stepping down, which would culminate in the election of his successor as president this fall. But anti-government protesters appear to have been dissatisfied by Mubarak's timeline, clashing violently on Wednesday with pro-Mubarak demonstrators on Egyptian streets.

The Obama administration has been urging Mubarak to begin the process of stepping down "now," in the words of the president in a statement last night.

"Now means now," White House press secretary Robert Gibbs said at his daily press briefing on Wednesday

The New York Times reported Wednesday that Obama's statement infuriated the government in Cairo, which saw it as in contradiction with Mubarak's call for an orderly transition. The Times also reported that the pro-Mubarak demonstrators were unleashed on the anti-government protestors gathered in Cairo's Tahrir Square, the epicenter of the revolt against the Egyptian president.