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.

Former Russian President Medvedev calls for preemptive strikes while Trump gives Putin a 50-day ultimatum to reach peace with Ukraine or face sanctions.

US President Donald Trump’s 50-day pause ahead of possible secondary sanctions on Russia gifts the Kremlin a window to exploit the incremental gains of recent weeks in Ukraine’s east.

Fossil fuel revenues form the backbone of Russia's economy, which has been buffeted by sanctions following Vladimir Putin's full-scale invasion of Ukraine.

KYIV, Ukraine — Russian President Vladimir Putin is “not ready for compromises” to end his brutal war, Ukrainian President Volodymyr Zelensky told The Post in an exclusive interview on Wednesday — but President Trump has the power to bring him to his knees by speeding up tough sanctions that could cause a “social explosion” in Russia.

Russian officials and commentators have shown little indication that Moscow is about to change course under new pressure.

Senate Majority Leader John Thune says Republicans will vote on a Russia sanctions bill once Trump approves it, as pressure mounts on Moscow to negotiate peace in Ukraine.

A Russian official says American Daniel Martindale has been rewarded with citizenship for spying on Ukraine, "by decree of our President Vladimir Putin."

President Trump told reporters that Ukraine should not target Moscow following a report that he advised Ukraine to ramp up its attacks.

By Elena Fabrichnaya MOSCOW (Reuters) -Prolonged high interest rates in Russia may drive mergers and acquisitions of distressed assets, a study by leading law firms showed, though Western-led sanctions and a liquidity shortage among buyers are likely to restrain growth in deals for now.