Ukraine and Russia: What you need to know right now

AIR raid sirens sounded across Ukraine before dawn on Tuesday as Ukrainian and Russian negotiators prepared to meet in Turkey for face-to-face talks, with Kyiv seeking a ceasefire without compromising on territory or sovereignty.

FIGHTING

* Russia continues missile and bomb strikes in an attempt to completely destroy infrastructure and residential areas of Ukrainian cities, said Ukraine military general staff.

* Russia said it destroyed large ammunition depots in the Zhytomyr region and hit 41 Ukrainian military sites in the past 24 hours.

* Ukraine said it seized back control of Irpin, near Kyiv. A U.S. official said the eastern town of Trostyanets, south of Sumy, was back in Ukrainian hands. Reuters could not confirm the reports.

* Russian soldiers who seized the Chernobyl site drove armoured vehicles without radiation protection through a highly toxic zone called the "Red Forest", workers there said.

TALKS AND DIPLOMACY

* Russian billionaire Roman Abramovich and Ukrainian peace negotiators suffered symptoms of suspected poisoning after a meeting, the Wall Street Journal reported. But a U.S. official said intelligence suggests the symptoms were due to an environmental factor, not poisoning.

* The Kremlin said Joe Biden's remark that Putin "cannot remain in power" was a cause for alarm. Biden said the comment reflected his own moral outrage, not a U.S. policy shift.

* Ukrainian President Volodymyr Zelenskiy urged Western nations to toughen sanctions including an oil embargo.

CIVILIANS

* The U.N. human rights office said 1,119 civilians had been killed and 1,790 wounded since Russia began its attack.

* Nearly 5,000 people, including about 210 children, have been killed in besieged Mariupol, a spokesman for its mayor said.

ECONOMY

* Russia said it would not supply gas to Europe for free as it worked out methods for accepting payments for its gas exports in roubles. G7 nations refused the demand.

* U.S. and German officials are due to meet in Berlin this week with energy industry executives to discuss ways to boost alternative supplies for Germany.

* Russia's invasion has cost Ukraine $564.9 billion in terms of damage to infrastructure, lost economic growth and other factors, Economy Minister Svyrydenko said.

QUOTES

* "We are not trading people, land or sovereignty," Ukrainian Foreign Minister Kuleba said of the talks in Turkey.

* "We have destroyed the myth of the invincible Russian army," Kyiv Mayor Klitschko said.