President Barack Obama used an Asia-Pacific summit on Saturday to push back against China's trade practices, insisting Beijing stop poaching U.S. intellectual property and allow its currency to rise.

Obama, under pressure to create jobs at home and eager to highlight U.S. influence abroad, said an undervalued Chinese yuan was putting U.S. businesses at a disadvantage and a change in the currency policy would help the global economy.

What I have said since I first came into office and what we've exhibited in terms of our interactions with the Chinese is we want you to play by the rules. And currency is probably a good example, Obama said at a forum of global executives on the sidelines of the Asia-Pacific Economic Cooperation summit.

For an economy like the United States -- where our biggest competitive advantage is our knowledge, our innovation, our patents, our copyrights -- for us not to get the kind of protection we need in a large marketplace like China is not acceptable.

Obama spoke shortly after Chinese President Hu Jintao took the podium at the gathering of executives. Hu told them Beijing was committed to free trade in the Asia-Pacific region and urged mutual respect in global decision-making.

The two presidents, leaders of the world's two largest economies, were due to meet one-on-one later on Saturday.

Obama is under pressure from Republican presidential candidates, including front-runner Mitt Romney, to take a tougher line with China. Obama's remarks on Beijing's trade practices seemed more pointed than in the past.

But U.S. leverage over Beijing is limited since China is the largest foreign creditor of the United States, holding more than $1.1 trillion in U.S. debt.

Obama called for reciprocity in the trade arena, saying there was no reason this should lead to problems in broader relations. But he said the United States would speak out and in some cases we'll take action if rules were being broken.

Obama told the business leaders the United States was putting a priority on the fast-growing Asia-Pacific region.

On Europe, he offered guardedly optimistic predictions that it would work its way through its fiscal problems.

There have been positive signs in Europe's efforts to tackle its debt crisis, with leaders focused not just on Greece but on problems affecting the euro zone more broadly, Obama said.

He said Italy's troubles could not be fixed overnight but it was important Europe stand behind its euro zone members.

I was pleased to see that European leaders were taking seriously the need to not just solve the Greek crisis but also to solve the broader euro zone crisis, Obama said.

(Additional reporting by David Lawder; Editing by John O'Callaghan)