Deadly strikes rock Ukraine despite talks with Russia

Russia unleashed a barrage of air strikes Monday on cities across Ukraine as the warring sides traded blame for a deadly attack in a pro-Moscow separatist region -- but made little headway in ceasefire talks.

With Russian forces threatening to take "full control" of several major cities, the fourth round of talks failed to deliver a breakthrough on the 19th day of the invasion, with negotiations to resume on Tuesday.

On the international front, high-ranking US and Chinese officials met for a marathon seven hours of talks, as the United States raised the alarm about a possible Chinese "alignment" with Russia -- which the West wants to isolate over the invasion of its ex-Soviet neighbour.

The talks, which follow reports Moscow asked Beijing for military and economic assistance as its troops struggle to make ground in Ukraine, were described by a senior US official as "very candid" -- diplomatic code for a feisty exchange.

The United Nations estimates almost 2.8 million people have fled Ukraine since President Vladimir Putin launched a full-scale land and air assault on February 24. It has recorded more than 600 civilian deaths, including dozens of children, though the true toll could be far higher.

Putin's effort to control the narrative over the deadly conflict suffered a blow Monday when a dissenting employee entered the studio during Russia's most-watched evening news broadcast, holding up a poster saying "Stop the war. Don't believe the propaganda."

An opposition protest monitor says the woman, an editor at the tightly-controlled state broadcaster Channel One, was detained following the highly unusual breach of security.

And on the opposing side of the information war, congressional leaders in Washington announced that Ukraine's President Volodymyr Zelensky would deliver a high-profile virtual address to both chambers on Wednesday -- as US lawmakers seek to ratchet up pressure on the White House to take a tougher line over Russia's invasion.