Stocks wrapped up the session on a high note, with the Dow logging triple-digit gains, after Federal Reserve Chair Janet Yellen said there's still room for the central bank to help the economy. But major index ended relatively flat for the first quarter.
Ukraine on Monday denounced the visit of Russian Prime Minister Dmitry Medvedev to Crimea.
U.S. stock index futures pointed to a higher open on Monday, with global shares boosted hopes of stimulus in both the euro zone and China.
April could be the cruelest month for stocks so far this year if warmer weather doesn't reverse a trend of weaker economic data.
Defying Ukrainian protests and Western sanctions, Russian President Vladimir Putin signed a treaty in Moscow on Tuesday making Crimea part of Russia.
Moscow shipped more troops and armor into Crimea on Friday, showing no sign of bowing to Western demands to pull back.
Secretary of State John Kerry had an in-depth conversation with Russian Foreign Minister Sergey Lavrov on how to best resolve the Ukraine crisis. Kerry said, "We believe the referendum is contrary to the constitution of Ukraine and a violation of international law."
CNBC's Michelle Caruso-Cabrera discusses the looming Crimean referendum and reports on increasing violence in the eastern part of Ukraine.
Tensions around Ukraine will dominate markets Friday as diplomatic efforts are expected to generate buzz ahead of Sunday's referendum in Crimea.
Stocks tumbled amid concerns events surrounding Ukraine are escalating and China's slowing growth will rub off on the global economy and bite corporate profits.
CNBC's John Harwood discusses the meeting between Secretary of State John Kerry and Russian Foreign Monster Sergey Lavrov.
Gen. Mark Kimmitt, U.S Army (Ret.) and former assistant Secretary of State, and Barry Pavel, Atlantic Council vice president, discusses the sentiment of the U.S on Russia's open option to force in Ukraine.
As political tensions rise, the cooperation between the U.S. and Russia in the energy industry is large and growing, experts at IHS CERAWeek say.
U.S. bonds fell on Tuesday, as investors' "safe-haven" bid waned, due to signs of progress in resolving the political turmoil in Ukraine.
CNBC's Ian Williams reacts to Secretary of State John Kerry and President Obama's comments regarding the conflict in Ukraine. The two offered a "comprehensive rebuttal" of Putin's earlier statement, says Williams.
"(The) Russian government ... has chosen aggression and intimidation as a first resort," Kerry said in a news conference in Ukraine's capital.
Secretary of State John Kerry says the people of Ukraine have the right not to go back to life as it was under former President Viktor Yanukovych and the United States stands with the people of Ukraine. The U.S. has offered $1 billion in a loan guarantee to support Ukraine's recovery.
CNBC's Michelle Caruso-Cabrera discusses what kind of assistance the U.S. is prepared to offer Ukraine.
Despite the ongoing turmoil in Ukraine, Wall Street looked set to rebound on Tuesday, following the worst day for markets in a month.
CNBC's Michelle Caruso-Cabrera discusses how the global markets are reacting to Vladimir Putin's comments on Ukraine. Also, Secretary of State John Kerry arrives in Kiev today.