Main news of April 21

A roundup of what has happened in the past 24 hours

WORLD

In a dramatic sign of improving ties, Moscow and Kiev agreed to extend the lease on a Russian naval base in the Crimea in exchange for a 30% cut in gas prices for Ukraine

* Ukrainian President Viktor Yanukovych should be impeached for signing an agreement extending Russian naval presence in the Crimea for 25 years after 2017, because it contradicts the Ukrainian Constitution, a statement by pro-western Ukrainian Viktor Yushchenko's party said

* North Korea said it would not abandon its nuclear weapons program, but was ready to take part in non-proliferation efforts together "with other nuclear weapons states," South Korea's Yonhap agency said

* Ousted Kyrgyz President Kurmanbek Bakiyev should participate in Kyrgyz presidential elections, Belarus President Alexander Lukashenko said

* Iran's Revolutionary Guards will conduct a three-day military exercise in the Persian Gulf starting Thursday, a top military official said.

* Ousted Kyrgyz President Kurmanbek Bakiyev has denied claims made by the Central Asian Republic's interim government that he has resigned from his post as president and said was ready to answer to the law

* Kyrgyz interim Prime Minister Roza Otunbayeva has ordered police to shoot and kill looters in the ex-Soviet Central Asian republic

* Polish acting president, parliamentary speaker Bronislaw Komorowski has set a date for early presidential elections in Poland on June 20, Sunday, the official Polish Parliament website said

* Talks in Moscow on U.S. adoptions of Russian children have been postponed until April 29-30, a U.S. State Department spokesman

* The new strategic arms reduction pact signed by Russia and the United States in Prague is to be submitted to the countries' parliaments in May

RUSSIA

* Russia will sign an agreement with France on the purchase of a Mistral-class helicopter carrier by yearend, the head of the Federal Service for Military and Technical Cooperation said

* Conscripts in the Russian armed forces will have a five-day working week and civil workers will be hired to cook food and clean, Russian Defense Minister Anatoly Serdyukov said

BUSINESS

* State Technology Corporation Rostekhnologii plans to establish a joint venture with Israel Airspace Industry for the production of unmanned aerial vehicles (UAVs), the Russian corporation's head said

* Russia's energy giant Gazprom and Ukraine's Naftogaz signed addenda to contracts on Russian natural gas transit via Ukraine for 2009-2019 and on the sales of gas

Recent flight disruptions caused by the Icelandic volcano eruption have cost airlines more than $1.7 billion in lost revenues through Tuesday, the International Air Transport Association (IATA) said

* Moscow may within five years create an international financial center, able to compete with Dubai and Shanghai, Russian business daily Vedomosti said citing experts

* China National Petroleum Corporation (CNPC) will pay Venezuela $900 million for access to heavy crude oil fields in the Orinoco River Basin, Venezuela's Oil Minister Rafael Ramirez said

SPORTS

* Russian President Dmitry Medvedev expressed his deepest condolences over the death of former President of International Olympic Committee Juan Antonio Samaranch, who passed away at the age of 89