France is standing with the United States in condemning Israeli construction in east Jerusalem.
French President Nicolas Sarkozy said his own commitment to Israel's security is well known, but added that the "settlement" activity in an area claimed by the Palestinians "contributes nothing."
Speaking at a news conference with President Barack Obama after their White House meeting Tuesday, Sarkozy praised Obama for trying to engage the two sides in peace talks. Sarkozy said the "absence of peace" in the region "is a problem for all of us" - and that it feeds terrorism around the world.
Obama, for his part, told reporters he would like to see new UN sanctions placed on Iran in a matter of weeks.
"My hope is that we are going to get this done this spring," said the US leader. "I'm interested in seeing that regime in place in weeks."
China, reluctant for months, is believed to be slowly falling in line in backing the idea of new sanctions.
Sarkozy said "the time has come to take decisions" on Iran and that with German Chancellor Angela Merkel and British Prime Minister Gordon Brown, "we will make all necessary efforts to make sure that Europe as a whole engages in the sanctions regime."
The United States and its allies believe Iran is seeking to develop a nuclear weapon, a charge Tehran denies.
Obama said the long-term consequences of a nuclear-armed Iran are unacceptable and that Tehran had so far rejected diplomatic entreaties.
"The door remains open if the Iranians choose to walk through it," he said.
Also Tuesday, diplomats from the world's leading economies said Iran's recent actions deepen the doubts that its nuclear program is aimed at anything other than building a bomb, and US Secretary of State Hillary Rodham Clinton predicted that world powers will agree on a new round of UN sanctions.
Closing a conference of foreign ministers from the G-8 industrialized nations, Canadian Foreign Minister Lawrence Cannon said it is time to act.
Clinton said the nations meeting in Canada see a growing alarm around the world about the consequences of a nuclear-armed Iran.
Earlier, Obama told MSNBC that the underlying relationship between the US and Israel is "solid as a rock" despite the recent diplomatic rift over Israel's decision to build additional housing units in east Jerusalem.
He said Israeli Prime Minister Benjamin Netanyahu "intellectually understands that he has got to take some bold steps" and that the Palestinians have to do the same. "This is a disagreement among friends about how to move forward," Obama added.
Yitzhak Benhorin contributed to the report