Obama visited Afghanistan during the 2008 campaign, but the then-Illinois senator was part of a larger congressional delegation.
Romney visited Afghanistan in 2011. Aides said he's skipping it this time because of a tight schedule.
Throughout the trip, Romney will face inevitable comparisons with Obama, whose overseas trip to seven countries during the 2008 campaign culminated with a speech to an audience of 200,000 at the Victory Column in Berlin.
At his first stop, in London, Romney plans meetings with British Prime Minister David Cameron, Deputy Prime Minister Nick Clegg, Chancellor of the Exchequer George Osborne, Foreign Secretary William Hague, and Ed Miliband, who leads the opposition Labour Party. He plans fundraisers, where attendees will likely include bankers and others from London's financial sector.
Great Britain is America's most important global ally, and the special relationship between the two countries is a primary focus for any new president or secretary of state. Typically, meetings with British leaders are among the first any new American leader holds after taking office.
The Olympics, kicking off July 27 in London, could also offer Romney opportunities for additional meetings with foreign leaders, many of whom will be there for the beginning of the games. Romney advisers said efforts continue to set up additional meetings.
Romney plans to attend the Olympic opening ceremonies and some of the early competitions. The events offer Romney an opportunity to highlight his record at the 2002 Winter Games in Salt Lake City, where he was brought in to run the organizing committee following a bribery scandal. So far, he hasn't talked much about his role at the Olympics on the campaign trail, and it's been mostly absent from his TV commercials. That's likely to change in London, where Romney plans a major interview with NBC News' Brian Williams.
Romney isn't part of the official U.S. presence at the international competition. First lady Michelle Obama will lead the U.S. delegation.
In Poland, Romney will visit a deeply Roman Catholic country that for years has favored Republicans over Democrats. The visit, campaign officials said, comes at the invitation of Lech Walesa, the Polish labor leader who co-founded the Solidarity movement and served as Poland's president during the country's transition out of communism. Romney will meet with Walesa in the Solidarity birthplace, Gdansk, and also hold meetings in Warsaw.
In Poland, Romney will have an opportunity to criticize Obama's so-called political "reset" with Russia after U.S.-Russian ties deteriorated badly under President George W. Bush, as well as the Obama administration's decision not to build a missile defense base in Poland.
Romney has referred to Russia as America's "No. 1 geopolitical foe."
He'll likely receive a warm welcome. Poles have never showed the enthusiasm for Obama that Germans and other Western Europeans did, and his popularity there has declined further during his years in office. But for Romney, the critical audience for his Poland trip is likely the many U.S. citizens with Polish ancestry who live in critical swing states across the American Midwest.
Associated Press Deputy Polling Director Jennifer Agiesta in Washington and writer Vanessa Gera in Poland contributed to this report.
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