HEILIGENDAMM, Germany — After a torrent of sharp exchanges, President Bush tried to stop a steep slide in relations with President Putin yesterday by saying Russia is not a menace to Europe despite a threat to aim missiles at the West.

“Russia is not going to attack Europe,” Mr. Bush said, brushing off Mr. Putin’s warning that he would reposition Russian rockets in retaliation for an American-devised missile shield to be based in Poland and the Czech Republic.

“Russia is not an enemy,” Mr. Bush emphasized. “There needs to be no military response because we’re not at war with Russia.”

A day before meeting privately with Mr. Putin here, Mr. Bush appeared eager to call a time-out in the bickering over everything from criticism about Russia’s backslide on democracy to Mr. Putin’s complaints about U.S.-backed independence for Kosovo and a supposed new arms race triggered by Washington.

“There will be disagreements,” Mr. Bush said, relaxing in the sun during an interview with a handful of reporters before the annual summit of major industrialized countries. “That’s just the way life works. But that doesn’t necessarily lend itself to speculation that somehow the relationship between me and the president [Mr. Putin] is not a positive relationship. It is a positive — and I’m going to work to keep it that way.”

Asked if he expected a tense session with Mr. Putin, Mr. Bush said, “Could be — I don’t think so, though. I’ll work to see that it’s not a tense meeting.”

Mr. Bush, tieless and with his shirt sleeves rolled up, sat for the interview just hours before the opening of the Group of Eight summit with Germany, Canada, Britain, France, Italy, Japan, America, and Russia.

The leaders gathered in Heiligendamm, a Baltic Sea town in northern Germany that was circled by 7 miles of razor wire-topped fence.

Thousands of demonstrators blocked roads to the summit site, and thousands more streamed toward the fence. Police used water cannons to scatter stone-throwing protesters.

At a pre-summit lunch, Mr. Bush discussed combating global warming and poverty in Africa with Germany’s Chancellor Merkel, the summit host. She advocates a tougher stand on climate change than Mr. Bush.

Ms. Merkel said they had a “very good debate … but I trust that we will work out joint positions.”

In the interview, Mr. Bush said he would not yield to Ms. Merkel’s proposals for mandatory caps on greenhouse gas emissions. Mr. Bush has countered with a plan for negotiations between America and other nations that spew the most greenhouse gases — including China and India — to set a long-term strategy by the end of next year for reducing emissions. American officials said Mr. Bush was willing to move more quickly to set goals.

Jim Connaughton, chairman of the White House Council on Environmental Quality, said an agreement on global warming was “almost done.”

Mr. Bush also met with new Japan’s Prime Minister Abe and discussed North Korea’s pledge to close its sole nuclear reactor in exchange for economic aid and political concessions.

“There is a common message here and that is: We expect North Korea to honor agreements,” Mr. Bush said. In the interview, Mr. Bush offered his case for why Russia should not worry about a U.S. missile shield in Europe.

The shield could defend against only one or two rocket launchers, Mr. Bush said. “Russia has got an inventory that could overpower any missile defense system,” he said. “The practicality is that this is aimed at a country like Iran, if they ended up with a nuclear weapon, so that they couldn’t blackmail the free world.”