President Obama arrived in Seoul, South Korea, Friday to news that North Korea may be counting down to a nuclear weapons test.
Such moves out of Pyongyang are no surprise and are typical for the North's behavior, Obama told reporters while in Tokyo, his previous stop on his Asia trip.
The President said he is prepared to deliver a firm response, if a test is conducted during his visit.
North Korea's heightened activity at its nuclear test site was already known. But now the final step needed for an underground detonation has been taken, a South Korean government official said Thursday.
The North has closed off the entrance to the tunnel at the Punggye-ri nuclear test site, the official said.
That gives Pyongyang 11 days to either detonate a nuclear device or cancel the test. It would be the North's fourth test of a nuclear weapon.
We're expecting a live news conference from the President within the hour. We'll bring it to you when it starts on "Early Start."
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President Barack Obama is ready to talk even on Republicans' terms, he insisted Tuesday, so long as Congress acts first to end the government shutdown and raise the debt ceiling - even for a short period.
At a news conference, Obama indicated Republicans could essentially set the agenda for budget negotiations, but only if Congress agrees first to a short-term spending plan to fund the government and to raise the federal borrowing limit to avoid a possible first-ever U.S. default next week.
"I will talk about anything," the president said.
Is it a glimmer of hope, or more rhetoric as the deadline for possible government default gets closer?
After weeks of near silence without any hint of a potential compromise between the Obama administration and congressional Republicans over raising the nation's debt ceiling, the White House may be offering some conciliatory language that could help lead to a deal to prevent a potential default on October 17.
As recently as Friday, White House officials declined to specify any demand for the length of a deal to increase the nation's debt ceiling.