With Afghanistan's election crisis deepening, Sen. John Kerry says it would be irresponsible for the U.S. to consider sending additional troops to the region at this time.

In taped remarks to air Sunday on CNN's "State of the Union," Kerry said it would be misguided to have a troop buildup to achieve a mission of "good governance" when the election is not yet finished.

Kerry, who chairs the Senate Foreign Relations Committee, was in Kabul on Saturday.

His visit came as Afghanistan's president, Hamid Karzai, resisted international pressure to accept fraud rulings that could force him into a runoff with his main challenger, Abdullah Abdullah. Due to harsh weather, a runoff may not happen until next spring.

Three more American service members were reported killed in separate bombings as the U.S. and its international partners sought a way out of Afghanistan's political impasse, a crisis that threatens the legitimacy of the Afghan government and the future of the U.S.-led military mission.

A U.N.-backed panel had been expected to release findings Saturday from its investigation into allegations of widespread fraud -- most of it favoring Karzai -- in the Aug. 20 election. Preliminary figures showed Karzai won with more than 54 percent of the vote.

Still, Karzai could face a runoff with his chief rival, Abdullah Abdullah, if the complaints panel invalidates enough ballots to push the incumbent's total below 50 percent.

Announcement of the commission's findings was delayed as commission members spent Saturday in meetings with Afghan election officials and double-checking calculations, according to people familiar with the talks.

Karzai has refused to commit to accepting the panel's findings before they're released, even though his campaign staff has expressed confidence that the president will remain above 50 percent, eliminating the need for a runoff.

Karzai's stand has raised concern that he may challenge the findings, further delaying proclamation of a winner or the scheduling a runoff.