Warsaw, Poland (CNN) Frankly acknowledging a "tough week" in the United States after anxious days of shootings and racial tensions, President Barack Obama said Saturday that he did not believe the United States was "as divided as some have suggested."

"There is sorrow, there is anger, there is confusion about next steps," Obama said during a news conference in Poland. "But there's unity in recognizing that this is not how we want our communities to operate. This is not who we want to be as Americans."

Speaking for the third time in Poland about the gun violence that's seized communities in the United States, Obama said the situation didn't resemble the periods of mass social unrest in the 1960s.

"You're not seeing riots, you're not seeing police going after people who are protesting peacefully," he said.

But he acknowledged a ramped-up anxiety that's descended on Americans as they watch seemingly unfettered violence on urban streets.

"Americans of all races and all backgrounds are rightly outraged by the inexcusable attacks on police, whether it's in Dallas or anywhere else," Obama said. "That includes protesters, that includes family members who have grave concerns about police misconduct, and they've said this is unacceptable. There's no division there."

Obama didn't mention any critics by name, but on Friday, presumptive Republican presidential nominee Donald Trump said racial divisions in the country have "gotten worse, not better."

The President pushed back on that notion, insisting that Americans of all races were disgusted by gun violence.

Keeps up calls for greater gun control

Obama was speaking at the conclusion of a NATO summit, a meeting whose central themes were largely obscured both by the Dallas shootings and reaction to last month's Brexit vote.

He said the motives of the killer in Dallas were "very hard to untangle" but called the shooter "demented" and downplayed the potential political motivations he may have carried. The shooter allegedly voiced a desire to "kill white people" ahead of the attack, authorities have said.

"I think the danger is that we somehow suggest that the act of a troubled individual speaks to some larger political statement across the country. It doesn't," Obama said.

Referencing last year's attack on churchgoers in Charleston, South Carolina, Obama noted, "When some white kid walks into a church and shoots a bunch of worshipers who invite him to worship with them, we don't assume that somehow he's making a political statement."

And he made another call for tighter restrictions on guns, saying if Americans are concerned about violence against police officers, "you can't set aside the gun issue and pretend that that's irrelevant."

He voiced frustration at the bitter political debate over guns, lamenting that "even mention of it somehow evokes this kind of polarization."

"When it comes to the issue of gun safety, there is polarization between a very intense minority, and a majority of Americans who actually think that we could be doing better when it comes to gun safety."

Before the NATO sessions even began midday Friday, Obama had delivered two statements about violence back home, as well as addressed continental anxiety about Britain's decision to leave the European Union.

Aides said Obama recognized on his transatlantic flight to Poland that a more robust presidential response was needed in the wake of the killings of African-American men in Minnesota and Louisiana. He made a beeline for a podium in his hotel, arguing that African-Americans are more likely to be pulled over, arrested and shot at by police.

But it was only 10 hours later when Obama was back at the podium, this time condemning the sniper attack on police officers in Dallas. Even amid back-to-back meetings with European leaders, Obama pulled away to phone the city's police chief. Late Friday, after a working dinner had concluded, the White House announced he was scrubbing a planned stop in Seville, Spain, to return home early. He plans to visit Dallas early next week, and called Texas Gov. Greg Abbott from Air Force One on his way to Spain to offer his condolences on behalf of the American people, the White House said.

'We plant seeds'

For Obama, it was yet another example of his struggle to balance his symbolic stature as the first African-American president and the realities of a country still struggling with issues of race.

"What I hope is that my voice has tried to get all of us as Americans to understand the difficult legacy of race," Obama said of that struggle on Saturday. "To encourage people to listen to each other. To recognize that, you know, the legacy of slavery and Jim Crow and discrimination didn't suddenly vanish with the passage of the civil rights act or voting rights act or the election of Barack Obama."

"We plant seeds," Obama said of his attempts at promoting racial reconciliation. "And somebody else maybe sits under the shade of the tree that we planted."

While the Dallas attack diverted Obama's attention for at least some of the day, other leaders gathered in Poland were distracted by the still-uncertain future between Britain and the European Union. British Prime Minister David Cameron, seen chatting privately with Obama multiple times over the two-day summit, sought to soothe fears that his decision to allow a referendum on exiting the EU could destabilize the continent.

"While Britain may be leaving the European Union, we are not withdrawing from the world, nor are we turning our back on Europe or on European security," Cameron said Saturday.

Obama, in a meeting with the presidents of the European Union and the European Council, sought clarity on how the bloc would handle the divorce. Officials said he stressed the importance of finding a solution that could stabilize markets quickly.

"I think it was clear that people recognize just how important it is that this be done in a way that not upset financial markets, that not upset global economic stability," said Ben Rhodes, Obama's deputy national security adviser. "I think it was clear from the meeting that this is not going to be done in a way that is punitive towards the United Kingdom, but rather is about defining a new relationship."

Like on all of his foreign travel over the past year, Obama came to Poland expecting questions about his country's rancorous presidential contest. He has said some of the rhetoric emanating from Trump has harmed the United States' reputation abroad.

But more than before, Obama is confronting questions about how the undercurrents of anti-globalism in Trump's campaign — the same sentiments that helped propel the "leave" campaign to victory in Britain — could alter the way the U.S. does business.

In Poland, Obama barely mentioned the languishing transatlantic trade deal he hopes to finalize before leaving office, at least in public. In meetings, officials said Obama was intent on pressuring leaders to maintain pressure on Russia amid persistent aggressions in Eastern Europe and to bolster support for the prolonged mission in Afghanistan.