President Barack Obama is continuing his diplomatic slog in China Sunday, meeting with counterparts from the United Kingdom and Turkey -- two essential US allies -- as each leader confronts widespread internal strife back home.

It's the second day of high-stakes diplomacy for Obama, who arrived here Saturday to an inauspicious welcome: no red-carpeted stairs for Air Force One and open quarreling on the tarmac between Chinese and US officials over press access. Other leaders arriving for the G20 here were greeted with a far grander welcome.

The rancor continued throughout Saturday as Obama met with Chinese President Xi Jinping to cement a carbon reduction agreement and haggle over longstanding disputes like cybersecurity and maritime aggression.