WARSAW, Poland — Mitt Romney is stressing the United States' long ties with Poland as he caps a weeklong foreign tour designed to prove his leadership on world affairs and highlight his differences with President Barack Obama.

The Republican presidential candidate is readying a foreign policy speech for delivery Tuesday at the end of a three-nation tour that began last week in Britain and took him to Israel.

Romney stumbled along the way, inadvertently insulting Brits and angering Palestinians, and was left looking to Poland as a final opportunity to project the image of a leader ready to stand on the world's stage.

The two-day trip to Poland is aimed at Polish-American and Catholic voters in the U.S. and will highlight Romney's stance toward Russia. He has labeled Russia as America's "No. 1 geopolitical foe," a characterization that's not unwelcome in a country that still fears Russia. Poles generally have been skeptical of Obama's "reset" with Russia, and Romney has cited Polish concerns in his criticism of Obama.

He'll deliver his remarks in a deeply Roman Catholic country that for years has favored Republicans over Democrats. This is partly a legacy of President Ronald Reagan, whose efforts helped bring down communism across Eastern Europe, for which Poles remain grateful.

Poland has been a stalwart U.S. ally and significant contributor to military operations in Iraq and Afghanistan. As a former Soviet Bloc nation that has been subjugated by bigger European powers throughout history, it remains particularly worried about Russian policy.

Some in Poland and the neighboring Czech Republic were upset by the Obama administration's decision to revise the Bush-era missile defense plan for Europe, which included sites in both countries.

Romney's visit, campaign officials said, was 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.

Walesa effectively endorsed Romney when the Republican presidential candidate visited him Monday at the Artus Center in a historic neighborhood of Gdansk.

"I wish you to be successful because the success is needed to the United States, of course, but to Europe as well and to the rest of the world, too. So, Gov. Romney, get your success, be successful," Walesa told Romney through a translator.

Walesa suggested Romney's leadership was needed to restore America's position in the world.

Romney is set to meet with Polish Foreign Minister Radoslaw Sikorski on Tuesday before his speech

Walesa's backing is meant to influence Catholics and labor union members in the U.S. But Rep. Marcy Kaptur, D-Ohio, told reporters Monday that the Polish visit "is nothing more than a superficial diversion and a desperate attempt to pander to Polish Americans and Catholics across our country."

"This trip is not going to change the November election," she said.

Romney's visit to Poland was not without controversy.

Campaign officials said the visit to Poland came at the invitation of Walesa, but the current leadership of Solidarity distanced itself from the event and issued a statement critical of Romney on Monday.

Solidarity characterized Romney as being hostile to unions and against labor rights. It emphasized that it had no role in organizing Romney's visit and expressed support for American labor organizations.