By Matt Spetalnick
SEOUL (Reuters) - President Barack Obama made clear on Tuesday he expects election-year politics to prevent a breakthrough with Moscow on missile defense before 2013 as he staunchly defended remarks caught on camera the day before with Russian President Dmitry Medvedev.
Obama was overheard telling Medvedev on Monday that he would have "more flexibility" to deal with contentious arms-control issues after the November 6 U.S. election, drawing sharp criticism back home from his Republican foes.
Speaking on the sidelines of a global nuclear security summit in Seoul, Obama said he stood by his earlier comments, insisting it was a political reality that "everybody understands."
"I don't think it's any surprise that you can't start that a few months before presidential and congressional elections in the United States and at a time when they just completed elections in Russia," Obama told reporters with Medvedev at his side.
U.S. plans for an anti-missile shield have bedeviled relations between Washington and Moscow despite Obama's "reset" in ties between the former Cold War foes. Obama's Republican opponents have accused him of being too open to concessions to Russia on the issue.
In Monday's talks, Obama urged Moscow to give him "space" until after the November ballot and Medvedev said he would relay the message to incoming Russian president Vladimir Putin.
The unusually frank exchange came as Obama and Medvedev huddled together on the eve of the summit, unaware their words were being picked up by microphones as reporters were led into the room.
Obama, responding to a reporter's question on Tuesday during a break in the summit, said progress on complex arms control issues required dealings with the Pentagon and Congress to build bipartisan support and that 2012 was not a good year to get that done.
"The current environment is not conducive to these kinds of thoughtful consultations," Obama said. "I think we'll do better in 2013."
The Democratic president has faced stiff opposition from Republicans in Congress to his legislative agenda on everything from job creation to taxes. Republicans have already made clear they have no interest in cooperating on further arms reduction deals with Russia.
Republican presidential candidate Mitt Romney seized on Obama's earlier comment, calling it "alarming and troubling."
"This is no time for our president to be pulling his punches with the American people," Romney said in a campaign speech in San Diego.
As he was leaning toward Medvedev in Seoul on Monday, Obama was overheard asking for time - "particularly with missile defense" - until he is in a better position politically to resolve such issues.
"I understand your message about space," replied Medvedev, who will hand over the presidency to Putin in May.
"This is my last election ... After my election I have more flexibility," Obama said, expressing confidence that he would win a second term.
"I will transmit this information to Vladimir," said Medvedev, Putin's protege and long considered number two in Moscow's power structure.
The United States and NATO have offered Russia a role in the project to create an anti-ballistic shield which includes participation by Romania, Poland, Turkey and Spain.
But Moscow says it fears the system could weaken Russia by gaining the capability to shoot down the nuclear missiles it relies on as a deterrent.
It wants a legally binding pledge from the United States that Russia's nuclear forces would not be targeted by the system and joint control of how it is used.
(Reporting By Matt Spetalnick; Editing by Nick Macfie)