Misha Japaridze / AP

Prime Minister Vladimir Putin entering the Kremlin's St. George Hall for the president's state-of-the-nation address earlier this week. Putin said failure to ratify the New START could lead Russia to add nuclear weapons.

Prime Minister Vladimir Putin said in an interview released Wednesday that Russia might be forced to build up its nuclear forces against the West if the United States fails to ratify a new arms reduction pact reached earlier this year.

The warning was the second in as many days after President Dmitry Medvedev said Tuesday that failure to develop a joint European missile shield with NATO could create an arms race in the next decade and force the Russian military to deploy new offensive weapons near the borders of the security bloc.

If the United States Senate fails to ratify the New START treaty that Medvedev and U.S. President Barack Obama signed in April, Russia will have to start adding weapons, Putin said.

"That's not our choice. We don't want that to happen. But this is not a threat on our part," Putin said, according to an excerpt of an interview with CNN's Larry King, recorded Tuesday and posted on the CNN web site Wednesday. "We've been simply saying that this is what we all expect to happen if we don't agree on a joint effort there."

The hourlong interview — Putin's second with King and the U.S. broadcast legend's last with a foreign leader — will be aired at 5 a.m. Moscow time on Thursday. Ten years ago, King began his interview Putin, then in his first year as president, with a question that instantly became famous: "Who are you, Mr. Putin?"

The prime minister said in the new interview that the treaty, which is being stalled by several senior Republican senators, is in the United States' best interests and that ignoring it would be "very dumb."

Republican Senator Bob Corker, a member of the Foreign Relation Committee, said Tuesday that the White House had done a "good job" easing some of his concerns on the treaty and that a deal could be reached by the end of the year.

The other excerpts of Putin's interview were lacking major news, analysts said.

"Putin loves being two steps ahead of Medvedev as a newsmaker, but this time he just flabbily repeats old things," said Sam Greene, a researcher with the Moscow Carnegie Center.

Commenting on a WikiLeaks report purportedly quoting U.S. Defense Secretary Robert Gates as saying democracy in Russia has disappeared while power has become concentrated in the hands of the security services, Putin turned to his trademark "sovereign democracy" mantra.

"I want to give some advice to our colleagues: Don't interfere with the sovereign choices of the Russian people," he said.

Although the WikiLeaks reports are "no disaster," Putin said, one account describing his relation with Medvedev as that of Batman's to Robin is arrogant, unethical and "aimed to slander one of us."

Putin, the elder member of the ruling tandem and Medvedev's political mentor, did not specify whom he meant. Calls to Putin's spokesman, Dmitry Peskov, went unanswered Wednesday.

"Of course, he meant Medvedev. Being called Batman is quite flattering," independent political analyst Stanislav Belkovsky said.

Putin has regularly shown frustration with such comparisons, saying they are an attempt to sow conflict between him and Medvedev.