Barack Obama may not be having a one-on-one with Vladimir Putin this week, but other world leaders are still expected to give the U.S. president a hard time when they gather Thursday and Friday for the G-20 summit in St. Petersburg.

Suggestions by the U.S. Federal Reserve that it could soon start to curtail its monetary stimulus measures have created havoc with the markets and currencies of fellow G-20 members India, Indonesia, Turkey, Brazil and South Africa. Investors have rushed to pull out money on the expectation that the momentum that buoyed these countries over the past year would shift.

Putting the point diplomatically, Indian Prime Minister Manmohan Singh said as he left for the summit on Wednesday, "I will emphasize in St. Petersburg the need for orderly exit from the unconventional monetary policies being pursued by the developed world for the last few years so as to avoid damaging the growth prospects of the developing world."

Obama arrives in Russia on Thursday as Congress debates whether to back his plan to launch a military strike against Syria over its gassing of its own citizens. In Sweden on Wednesday, Obama said it was not he who first drew a "red line" against the use of chemical weapons, but world nations when they ratified a ban on using such weapons.

Russia's Putin has strongly opposed any military action and is arming Syria. The two were supposed to have a separate meeting but that was canceled over Russia's refusal to turn over alleged NSA leaker Edward Snowden on U.S. espionage charges.

Regarding U.S. Federal Reserve actions to prop up the economy, Obama won't be giving Singh or other unhappy leaders much comfort. Though he has not opposed the Fed actions, Obama does not control it.

"The U.S. Fed will always set monetary policy on what they think is best for the U.S. economy," says Mike Callaghan, a summit veteran who now directs the G-20 Studies Center of Australia's Lowy Institute for International Policy.

This U.S. ambivalence stands in marked contrast with recent G-20 summits where a sense of crisis in Europe and earlier, across the world's largest economies, fueled pledges of concrete action on stiffening rules for global banks, holding back on new trade barriers and restructuring the International Monetary Fund and World Bank.

"You clutch each other when you are falling off a cliff," says Alejandro Reyes, a G-20 veteran now teaching at the University of Hong Kong. "(Now) the embrace is not so tight."

Reyes and other observers say the summit communique may give a nod toward Singh's general line about an "orderly exit". This lack of substantive commitments will be a good thing, says Wesley Widmaier, who runs the G-20 studies program at Australia's Griffith University.

"These (currency) declines aren't that big a deal," he says, arguing that weakening against the dollar will increase the competitiveness of India and the other affected countries.

The summit communique also will likely feature language backing further global financial regulations and World Trade Organization talks, but the official sessions are expected to be dominated by each G-20 member's domestic economic changes.

Japan Prime Minister Shinzo Abe, for example, will talk about his plans to move forward with a sales tax hike and possibly another stimulus package, his finance minister said.

The White House has announced only one-on-one meetings with Chinese President Xi Jinping and French President Francois Hollande. .

Instead of Putin, Obama is pointedly to meet in St. Petersburg with gay rights activists who are seeking support for their fight against Russian recent legislation against "gay propaganda".

One G-20 leader, Australia's Kevin Rudd, isn't coming St. Petersburg at all even though his country is to host next year's summit, timing which would normally give him a prominent role in shepherding the proceedings at this year's running.

Rudd is facing a tough re-election this weekend, but his absence this time could change the calculus for leaders deciding whether to attend future events. "It's clearly not a good look for Australia," Callaghan says.