Continued sharp differences over the South China Sea saw the top diplomats of the United States and China refusing to yield an inch after a closed-door meeting in Washington on Tuesday, their third in a month.
In remarks at a joint press conference that were clearly meant for Beijing, US Secretary of State John Kerry urged all parties to cease expansion and militarisation of occupied features.
Meanwhile, Chinese Foreign Minister Wang Yi said Beijing hoped not to see "any more close-up military reconnaissance or the dispatch of missile destroyers", recent US operations in the South China Sea that have been slammed by China.
Mr Wang stressed that "non-militarisation is not the responsibility of one party alone", hinting that US freedom of navigation operations and military exercises are to blame, said Ms Bonnie Glaser, senior adviser for Asia at the Centre for Strategic and International Studies (CSIS).
While both top diplomats spoke of non-militarisation, Ms Glaser said neither side had been able to define the concept, thus making it "highly unlikely that progress will be made towards achieving it".
Mr Kerry, in particular, pointed out that both sides have "yet to find that road" forward, but welcomed China's "offer for dialogue because that is obviously the best way to resolve whatever tensions there are".
North Korea was another key issue addressed by both officials, who signalled that they were near agreement on a United Nations resolution against Pyongyang, after it conducted a nuclear test last month.
"Important progress has been made in the consultations, and we are looking at the possibility of reaching agreement on a draft resolution and passing it in the near future," Mr Wang said, though no further details were released.
Mr Kerry said other issues covered in the talks included cyber security, human rights, climate change and the situation in Syria.
Questions from the media, however, circled back to the South China Sea, in view of recent developments.
Last week, the US accused China of raising tensions by deploying surface-to-air missiles on Woody Island in the Paracels, which is also claimed by Vietnam and Taiwan. US officials said on Tuesday that Chinese fighter jets had also been deployed to the same island.
CSIS said in a report on Monday that satellite images showed a powerful radar system being installed in the Spratlys, another disputed chain, which could boost China's monitoring capability in the sea.
Echoing the CSIS report that such developments "could significantly change the operational landscape in the South China Sea", the top US commander in the Pacific said his fleet would continue freedom of navigation operations, citing the sea's importance to global trade.
"China is clearly militarising the South China Sea, and you would have to believe in the flat earth to think otherwise," Admiral Harry Harris told a Senate committee hearing. "I believe China seeks hegemony in East Asia."
Addressing a question on the radar at the press conference, Mr Wang said the media should look beyond China's activities and question why "advanced armaments and equipment emerging in the South China Sea, including the strategic bombers, the missile destroyers", have been disregarded.
Mr Kerry hinted that a radar installation, when linked to other signs of militarisation in the region, was of "great concern to those who... rely on the South China Sea for peaceful trade, commerce and use".
Mr Gregory Poling, director of the Asia Maritime Transparency Initiative at CSIS, said: "Its (China's) new high-frequency radar, like its 3,000m runways and missile deployments, is another piece of the puzzle towards China's long-term goal of establishing de facto control over the sea and airspace throughout the nine dash line."