New Ukrainian leader Petro Poroshenko urged pro-Russian rebels to stand down in his inaugural address following his swearing in as president Saturday in Kiev. 

Poroshenko, 48, urged pro-Russia separatists in the east to stop perpetrating violence and engage in a dialogue with the Ukraine government. However, he said he will not negotiate with people who he deemed as "gangsters and killers."

Poroshenko's inaugural address did not indicate that the Ukraine conflict shows any signs of abating, and the fighting between Ukrainian forces and pro-Russia insurgents continues in eastern regions. Ukrainian officials said the fighting has left more than 200 people dead, according to The Associated Press. 

In the address, Poroshenko spoke out against Russia's annexation of Crimea and offered a promise that Ukraine would regain control of Crimea. However, he did not offer any strategies as to how Ukraine will regain the peninsula that was given to the country by Soviet leader Nikita Khrushchev. 

Following the speech, Russian President Vladimir Putin ordered tighter security along Russia's border with Ukraine to prevent illegal crossings into the country. Ukraine has accused Russia of bringing in Russian militants to aid the pro-Russia rebels in Ukraine. 

The militants in the east denounced Poroshenko's speech, roundly rejecting the new president. 

"At the moment it's impossible for him to come [to Donetsk for talks]," Denis Pushilin, a leader of the self-declared Donetsk People's Republic, told The Associated Press. "Perhaps with security, a group, so people won't tear him to pieces."

Poroshenko said he would offer amnesty to rebels who do not "have blood on their hands." However, insurgent leader Valery Bolotov in Luhansk said he doesn't believe Poroshenko's promise. 

Both Luhansk and Donetsk declared autonomy from Ukraine when the regions seceded from the country in an election last month. 

The new president promised to broker peace but did not say whether Ukrainian forces will halt their offensive against insurgents. 

Russia has urged Ukraine to end military operations in the east and also called for insurgents to stop fighting in order to facilitate the delivery of humanitarian aid. 

Poroshenko is now the commander-in-chief of the military and also appoints foreign and defense ministers. 

Poroshenko is often referred to as the "Chocolate King" because of his success making billions as a candy tycoon. Poroshenko, who was elected May 25, replaces Oleksandr Turchynov, who was interim president after Viktor Yanukovych fled Ukraine following months of violent anti-government protests to remove him from power. 

The ouster of pro-Russia Yanukovych incited antagonism between Ukraine and Russia that had been brewing for years with native Russian speakers rejecting the new govenrment. 

Crimea was soon annexed by Russia after a secession referendum, which was widely considered to have been rigged by the Kremlin. 

Poroshenko's inauguration was attended by U.S. Vice President Joe Biden, Sen. John McCain and other U.S. representatives. Biden met with Poroshenko after his speech, telling him, "There is a window for peace, and you know as well as anyone that it will not stay open indefinitely. ... America is with you."

Biden also promised $48 million in additional U.S. aid to Ukraine to implement economic and constitutional reforms. Previously, Washington promised $50 million in "crisis response" aid to the country. 

Poroshenko also said he would seek parliamentary elections early. The current parliament, which was elected in 2012, are mostly Yanukovych supporters who are mostly opposed to the pro-Western views of Poroshenko. 

Also, the new president said Ukrainian would remain the main language in the country but said the country will allow the "free use of the Russian language."