This is what you need to know before the bell:
Donald Trump's 2018 Budget Proposal seeks to slash federal spending. The budget plans to cut $3.6 trillion worth of spending over 10 years
At least 22 people have been killed in a suicide attack at Manchester Arena in the U.K. Political parties in the U.K. have suspended general election campaign following the attack
Greece fails to reach a deal which would secure fresh bailout funds. If Greece does not receive the funds, it will risk defaulting on its debt repayment in July
OPEC will discuss whether to extend oil production cuts for six or nine months at this week's meeting. Kuwait's oil minister said that not all members support a nine month extension
Brazil's embattled President Michel Temer refuses to step down. Temer told critics "I will not resign. Oust me if you want."
This article was written by a staff member of TheStreet.