A tarmac tiff between US and Chinese officials over media access highlighted the gap between views on human rights and press freedom, US President Barack Obama said Sunday after the incident soured the start of a global summit.

China's government minders gave American National Security Advisor Susan Rice and other US officials trouble over press access to the US leader's arrival in the eastern city of Hangzhou.

The dispute concluded in a nationalistic eruption from one official, who shouted "This is our country! This is our airport!" at White House staffers as they tried to help American reporters position themselves to film Obama's arrival.

The outburst was caught on camera, in an awkward prelude to face-to-face talks between Chinese President Xi Jinping and his American guest.

Both leaders are eager to smooth over their differences and find areas of common cause as they seek to bolster their leadership credentials both abroad and at home.

The incident was not a first for China, Obama said during a press briefing with new British Prime Minister Theresa May.

"We think it's important that the press have access to the work that we're doing. That they have the ability to answer questions," he said, adding "we don't leave our values and ideals behind when we take these trips."

The differences are also on display in discussions with his Chinese counterpart, he said.

"When I bring up issues like human rights, there are some tensions there that perhaps don't take place when President Xi meets with other leaders."

Kerfuffles over press access are common in China, where the ruling Communist Party sees the media more as a tool for forwarding its political agenda than an independent check on governance.

The country tightly controls its journalism, regularly censoring reporting on issues it deems sensitive or unflattering.

Its approach is particularly apparent in Hangzhou, where a suffocating security presence is designed to avoid any disruption and protect China's large political and financial investment in the summit.

Nevertheless, Obama took the tarmac incident in good rumour, noting that the travelling White House juggernaut can be intimidating for any nation.

"Part of it is we also have a much bigger footprint than a lot of other countries," he said.

"We've got a lot of planes, a lot of helicopters, a lot of cars, a lot of guys. You know, if you're a host country, sometimes it may feel a little bit much."

Obama arrives in China for final visit as president
Hangzhou, China (AFP) Sept 3, 2016 - US President Barack Obama arrived in China on Saturday for his final visit as president, intent on cementing the "pivot" to Asia undertaken during his administration.

Obama was welcomed by an honour guard as Air Force One landed in the eastern city of Hangzhou, which is hosting the G20 summit of global economic powers.

But there was also tension on the tarmac, with angry words exchanged when a Chinese official remonstrated with National Security Advisor Susan Rice about where she could stand.

Hangzhou is under ultra-tight security, with a quarter of its residents encouraged to leave and potential troublemakers detained as the ruling Communist Party takes every measure to prevent any possible wrinkles.

Later Saturday Obama will hold private talks with Chinese President Xi Jinping at the city's picturesque West Lake, dotted with islands and a favoured subject for Chinese artists.

The meeting is expected to focus on the fight against global warming, after China on Saturday ratified the Paris climate accord and with the US tipped to follow suit, taking the pact a giant step forward.

Tackling climate change has become a bright spot in often difficult relations between the two powers.

But Xi and Obama will also discuss tensions in the South China Sea, where Beijing's territorial claims, and its construction of artificial islands in disputed waters, have set the region on edge.

On Sunday Obama is to hold talks with Theresa May for the first time since she became British prime minister in the wake of the landmark vote to leave the European Union.

Syria will shift into focus when Obama meets his Turkish counterpart Recep Tayyip Erdogan on the sidelines of the summit.

Relations between Washington and Ankara have soured following an attempted coup against Erdogan and Kurdish advances along Turkey's southern border.

Erdogan has accused the United States of harbouring a Turkish cleric he accuses of plotting the coup.

US officials insist they will extradite Fethullah Gulen if Turkey can present proof he was actually involved.

The spat has soured public perceptions of the United States in Turkey and risks undermining a deep security relationship between the NATO allies.

Tensions have been further strained by Turkey's bombing of Kurdish positions in northern Syria.

The targets included Kurdish groups that are backed by Washington and seen as integral to the fight against the Islamic State group.

Ankara accuses them of being in league with the Kurdistan Workers Party (PKK), a group which has claimed responsibility for deadly attacks inside Turkey.

Obama could also take the opportunity to meet with Russian President Vladimir Putin, as their foreign ministers work to reach a deal that would ease fighting around Aleppo.

After the G20 talks conclude Monday, Obama will travel to Laos which is hosting the Association of Southeast Asian Nations (ASEAN) summit.