OSWIECIM, POLAND, SEPT. 29 -- Vice President Bush examined evidence of the horrors of the Nazi Holocaust today in a solemn visit to the death camps at Auschwitz and Birkenau, paying tribute to the 6 million Jews who died here and at other Nazi extermination camps.

"The brutal and tragic horrors of Auschwitz serve as grim reminders of man's capacity for evil," Bush said later. "The denial of human rights -- the denial of human dignity -- leads ultimately to this, the attempted extermination of an entire people."

The vice president's walking tour of the Nazi camps was the highlight of his final day in Poland on a visit designed to improve U.S.-Polish relations and boost his presidential campaign. Before leaving Warsaw this morning, Bush acknowledged the political goal of his tour. Asked about the impact at home of his dramatic appearance with Solidarity leader Lech Walesa on a church balcony, Bush said, "I suppose the next question is how many relatives does he have in Iowa?"

Bush said he hired a campaign camera crew "to take good pictures of me in Poland" and said, "I hope it helps me with everybody."

He defended his talks with government, church and opposition leaders, saying they had left him with the "very distinct feeling" that "Poland has come out of a very difficult time and things are moving forward." He said "time will tell" whether the communist government of Gen. Wojciech Jaruzelski moves to adopt further political and economic reforms which the vice president urged it to take if Poland is to get additional international economic aid.

After Bush left Warsaw, Polish government spokesman Jerzy Urban announced that the two governments have agreed to exchange ambassadors for the first time since the suppression of Solidarity in December 1981. Urban said Deputy Foreign Minister Jan Kinast will become Warsaw's envoy in Washington, and that Poland has accepted John R. Davis Jr., now U.S. charge d'affaires in Warsaw, as ambassador.

Urban also gently chided Bush.

"The western press, especially the American press, said that Bush opened his presidential campaign in Poland," he said. "I am having trouble distinguishing which part of the visit was international politics by an American statesman and which part was internal American politicking in the context of the American election."

Bush had irritated the government yesterday with his open endorsement of Solidarity, the outlawed trade union, and his appearance with Walesa before a cheering crowd. Today, spokesman Urban renewed a line of criticism that the government has taken in recent months toward Walesa.

"It is often the case that politicians have connections to people in another country who are their clients," he said. "Those people are not necessarily politically important in the country."

Bush made no major breakthroughs in the impasse in U.S.-Polish relations during his visit, in which the Polish government is seeking additional international economic aid, and the United States is asking for further "visible" reforms toward political and economic pluralism. Bush said today he did find "common ground" on the need to improve relations and said, "I did find an openness -- a willingness to discuss economic and political reform. Indeed, some changes have been made . . . "

Bush said in response to a question that he favors restoration of Solidarity to full legal standing, although other officials have said U.S. policy has not been to insist on this. Urban rejected any role for Solidarity, saying, "We shall not try to treat ailments by again injecting the country with illnesses that have been cured."

Later today, Bush arrived under a cold rain at the bleak Nazi concentration camp here and was escorted through the barracks, gas chambers and crematorium by Casimir Smolen, the director of the camp museum and an inmate at Auschwitz in 1940-45. Bush viewed Soviet film, taken after Soviet troops liberated the camp, that documented the killing, including footage of a mass burial of victims in pine boxes. As he left the room, the vice president shook his head. "Strong," he said. "Wow. Powerful. That's something, isn't it?"

Among other exhibits, Bush viewed one of dozens of cans of the Zyklon B gas used to kill millions of Jews and others, and another showing how the Nazis used hair from their victims to make a burlap-like "haircloth." The Bushes appeared upset at some of the exhibits. Bush also examined the "Wall of Death" where thousands of Auschwitz inmates were murdered by SS guards with handguns.

Bush laid a wreath at the memorial at Birkenau and wrote in a guest book, "May the children of the future be spared the agony of this horrible past."

Later, in a ceremony marking the upgrading of the American Consulate in Krakow, Bush said of the slaughter of 6 million Jews, "Thank God courageous Poles, risking the lives of themselves and their families, sheltered tens of thousands of Jews from their Nazi enemies.

"Hundreds of thousands of Christians met their ends in the awful death camps . . . . Today we saw the cell of Father Maximilian Kolbe, who sacrificed his life for that of a fellow prisoner and was canonized by the Catholic Church."