The president could begin pushing for a new round of sanctions against Iran as early as January unless its leaders commit in earnest to dismantling their nuclear energy program, one White House official acknowledged on Sunday.

That informal deadline and threat -- one of the White House's strongest to date -- arrives about a week after Iranian President Mahmoud Ahmadinejad signaled he would build additional, domestic nuclear power plants and, in the process, reject what was supposed to be a landmark deal between Iran, the International Atomic Energy Association and the world community.

"Well, the president has said consistently -- and the international community has also said consistently -- that we would be able to see which way Iran wishes to go by the end of the year," Gen. James Jones, the White House's national security adviser, told CNN's "State of the Union."

"And that clock's ticking. The door is still open, but, unfortunately, the picture Iran is painting is not a good one," he added. "But we are still open to negotiations. The IAEA is still working feverishly to try to bring this about."

The White House's relationship with Iran seemed to be improving as recently as a month ago, after Iranian leaders signaled they would permit inspections of their nuclear facilities and consider a deal to import nuclear energy from a third party.

But those negotiations quickly broke down. Iran's support for the deal during an October meeting of the P5+1 -- a team of British, Chinese, French, German, Russian and U.S. negotiators that met with Iranian leaders -- never truly materialized, prompting world leaders to worry the deal itself was doomed.

But the standoff reached a new intensity when Ahmadinejad decided he would no longer halt uranium production at Qom -- the secret nuclear facility world leaders rebuked Iran for constructing in October. The Iranian president also announced last week his state would construct 10 additional nuclear power plants; a clear message to IAEA officials and western leaders that it was frustrated with nuclear negotiations.

U.S. officials subsequently announced they would confer with European leaders in the hopes of assembling some sort of sanctions package. While some White House advisers acknowledged off the record last week they were making progress on that front, they added their proposed sanctions were still too irresolute to announce formally.

But Jones' remarks on Sunday nevertheless demonstrate the White House is seriously mulling a rebuke for Iran's nuclear program, unless Ahmadinejad returns to the negotiating table before next year.

"What's on the table is very logical, very fair, very reasonable," Jones said of the IAEA deal. "And if Iran wanted to signal to the world that it wishes to participate more fully in the family of nations, this is a very, very good way for them to do this."