U.S. President Donald Trump's decision to ramp up arms shipments to Ukraine is a signal to Kyiv to abandon peace efforts, Russia said on Thursday, vowing it would not accept the "blackmail" of Washington's new sanctions ultimatum.

President Trump asked Ukrainian President Volodymyr Zelensky whether Kyiv was able to hit Moscow and St. Petersburg, according to a senior Ukrainian official familiar with their exchange in a July 4 phone call.

A new plan to funnel billions in "top of the line" weapons is his most forceful backing of Ukraine yet, writes Daniel Fried.

Zelenskiy's choice of a young economist, Yulia Svyrydenko, well known in Washington, reflects the importance of repairing relations with the Trump administration after Zelenskiy's disastrous White House visit in February.

Mass attack hits cities overnight as Ukrainians brace for 50 more days of Russian terror * Putin unfazed by Trump's threats, plans to fight on in Ukraine, Reuters reports * Patriot missiles bound for Ukraine already being shipped,