MOSCOW – Prime Minister Vladimir Putin climbed into a firefighting plane Tuesday and dumped water on two of the hundreds of wildfires sweeping through western Russia and cloaking Moscow in a suffocating smog.

Putin has been a very visible leader in the battle against the fires, which have caused billions of dollars in damage and left thousands homeless in the past two weeks. He has demanded that soldiers help overstretched firefighting brigades and has walked through smoldering villages, consoling residents and promising them new homes by fall.

But with his once sky-high approval ratings dropping — and sociologists warning that discontent could grow as the fires and a severe drought take their toll — Putin has not let up.

He took off Tuesday in a Be-200 firefighting plane and then moved into the copilot's seat. Television footage showed him pushing a button to unleash water on blazing forest fires about 120 miles (200 kilometers) southeast of Moscow.

After hitting the button, Putin glanced toward the pilot and asked, "Was that OK?"

The response: "A direct hit!"

The stunt was classic Putin. In past years, he has copiloted a fighter jet, ridden a horse bare-chested in Siberia and descended to the bottom of Lake Baikal in a mini-sub. Just last month he drove a Harley Davidson motorcycle to a biker rally.

All of his exploits have been widely publicized on the national television networks, which are under government control. Russia holds its next presidential election in 2012, and Putin would be eligible to run.

Damage from the fires was expected to hit $15 billion, or about 1 percent of Russia's gross domestic product, the business newspaper Kommersant reported Tuesday. The government has yet to release any damage estimates.

The hottest summer since record-keeping began 130 years ago has cost Russia more than a third of its wheat crop and prompted the government to ban wheat exports. Putin said last week the ban would last through the end of the year, but his deputy said Tuesday the government may consider lifting the ban in October once the harvest is complete.

The government is eager to prevent a sharp increase in the price of bread, which could lead to greater public dissatisfaction. The agriculture minister, speaking Tuesday on Ekho Moskvy radio, reassured Russians that there was no reason to expect retail bread prices to rise.

The acrid smog that has engulfed Moscow for a week eased a bit Tuesday, but the concentration of pollutants remained high. Putin summoned Moscow Mayor Yuri Luzhkov, who said the situation in the capital was difficult but that city health authorities were doing what was needed to help people cope with the heat and smog.

Ambulances calls have risen by nearly a quarter, Luzhkov said.

The situation in Moscow was severe enough for the U.S. State Department to allow non-essential personnel and the families of all diplomats at the American Embassy to leave Russia temporarily at government expense. Spokesman P.J. Crowley said about 100 embassy staff and family members were eligible for the so-called "authorized departure" program.

The handling of the wildfire crisis could weigh heavily on approval ratings for Putin and President Dmitry Medvedev, the business daily Vedomosti cited a sociologist as saying.

Vedomosti noted that three polls conducted in July showed Medvedev's rating had dropped up to 10 percentage points since the start of the year, and Putin's had declined by up to 6 percentage points. The paper cited Leonty Byzov, a leading sociologist at the Russian Academy of Sciences, as saying the wildfires could drag those figures down even further and stoke anti-government protests.

The lowest approval ratings were reported by the independent Levada polling agency, which gave Medvedev 38 percent and Putin 44 percent. The highest were 52 for Medvedev and 61 for Putin, registered by the Public Opinion Foundation. The margin of error for the polls was about plus or minus 3 percentage points.

Sergei Gordeichenko, the head of the Forestry Agency for the Moscow region, was fired on Tuesday, following criticism from the president that he had not cut short his summer vacation to tend to the crisis.

Medvedev himself was slow to interrupt his Black Sea vacation even as fires around Moscow grew worse, and, unlike Putin — who went out in jeans to meet with sobbing villagers and exhausted firefighters — mostly conferred with officials after his return.

After his firefighting flight, Putin visited another village destroyed by fire and again promised residents that they would be fully compensated.

Putin also offered reassurances to residents of Moscow that something would finally be done about the dried-up peat bogs outside the city that often burn in the summer and where fires this year have sent out thick plumes of smoke. He said 300 million rubles ($10 million) would be allocated to flood the peat bogs.