WASHINGTON — As North Korea said Tuesday that it was ready to launch a long-range rocket later this week, prompting stern criticism from U.S. officials, experts said the planned launch revealed weaknesses in American policy toward the rogue nation.

Saying the launch would violate U.N. Security Council resolutions that bar North Korea from testing ballistic missiles, White House spokesman Jay Carney said the United States would "work with our partners on next steps if North Korea goes through with this provocation."

Speaking after a meeting with her Japanese counterpart, Secretary of State Hillary Clinton said Tuesday that the United States would pursue "appropriate action" against Pyongyang at the Security Council for an act that she argued would threaten regional security. Already, South Korea, Japan and the Philippines have gone on alert, with some airlines canceling or rerouting regional flights to steer clear of the rocket's trajectory.

The launch had been planned at least since last fall to coincide with the 100th anniversary of the birth of Kim Il Sung, the "Great Leader" and North Korea's first president, who died in 1994. Then, in February, the government of the new president, Kim's grandson, Kim Jong Un, struck a deal with the United States for 250,000 tons of food aid for the impoverished nation in exchange for shutting down its nuclear program and suspending long-range missile testing.

Last month, however, North Korea made it clear that it intended to go ahead with the "space launch" of a rocket carrying the Kwangmyongsong-3 satellite, which is intended to transmit data about weather conditions. North Korean officials have dismissed claims that the launch is a pretext for developing missile technology, but the United States, Britain, South Korea, Japan and other countries protested, and the Obama administration canceled the offer of food aid.

Last weekend, a South Korean intelligence report was leaked that indicated North Korea now was planning a separate underground nuclear-weapon test. On Sunday, North Korean officials gave a small group of Western journalists a rare peek at the site from which they'll launch their rocket later this week, perhaps as early as Thursday.

Experts said the apparent failure of the U.S. food deal illustrated how bilateral deals between Washington and Pyongyang — which didn't fully involve China — were problematic. While an offer of 250,000 tons of food is substantial, a report last year by the International University of Japan found that food aid from China — including handouts as well as food sold at discounted "friends' prices" — in most years far exceeds what the U.S. would have provided.

That means that in the minds of North Korean officials, the American food aid offer "has symbolic importance, but doesn't really matter much. They don't think they have much to lose," said one U.S. expert spoke only on the condition of anonymity because he works closely on negotiations between the countries.

On Tuesday, a Washington-based advocacy group, the Committee for Human Rights in North Korea, called on the United States to "provide food aid that reaches the hungry." But if the aid that's being withheld isn't seen as essential, it leaves the United States with little bargaining power, experts said.