Democratic Sen. John Kerry on Friday assailed President Bush's tax cuts as the latest congressional report showed that three rounds of reductions lowered taxes for the wealthy.

"Over the last four years, the burden of taxes has shifted from the wealthy to the middle class," the Democratic presidential nominee said at a front-porch event. "The middle class is paying more taxes."

The nonpartisan Congressional Budget Office, in a report released Friday, said that those in the top 1 percent of income got a bigger tax cut than those in the middle brackets. Kerry's economic platform calls for withdrawing tax cuts that went to those earning $200,000 or more, but Bush has said those tax cuts benefit small business and other job creators.

The Bush-Cheney campaign defended the president's tax policies and argued that Kerry has voted to increase taxes. "The president has lowered taxes for every American," said campaign spokesman Steve Schmidt.

Kerry also said Bush's policies in Iraq have contributed to rising oil prices.

"The world is unstable right now. The marketplace is unstable," Kerry said. "That hurts your jobs. That hurts your wallets.

Surging oil prices have been one factor driving down stock prices in recent days.

Kerry's campaign said increasing oil prices saps consumers' spending powers, eats into companies' profits and weakens consumer confidence. The campaign has criticized President Bush for promising to bring down the cost of gasoline by pressuring Middle Eastern oil-producing nations.

Bush campaign spokesman Steve Schmidt said the president has a plan to lower oil prices, decrease the nation's dependence on foreign oil and encourage development of renewable energy, but it's been blocked by Kerry and other Democratic senators.

"They'd rather play politics with high gas prices than do the hard work and help the president bring them down for the American people," he said.

Kerry has been touting a plan to reduce the nation's use of foreign oil by replacing a portion of it with renewable fuels like gas produced from corn and soybeans. "We're going to declare America energy independent," Kerry said to a crowd in Central Point, Ore.

The stops in Oregon mark the end of Kerry's two-week trek by bus, train and ferry across the country to visit battleground states. Bush also plans to campaign in Oregon on Friday.