Kosovo, considered by nationalists to be the medieval cradle of the Serbian state and religion, declared independence in 2008. Belgrade has pledged never to recognize the secession.
The EU brokered the tentative deal in Brussels on Friday in talks with the prime ministers of Serbia and Kosovo. The agreement would give Kosovo's ethnic Albanian leadership authority over rebel Kosovo Serbs. In return, the minority Serbs would get wide autonomy within Kosovo.
During an urgent session that started late Sunday, Kosovo's parliament voted in favor of a resolution to support the initial agreement.
The 120-seat legislature voted 89-5 early Monday to back the conclusions in the EU-brokered deal. The tense session was interrupted by hardline opposition members who oppose talks with Serbia.
About 200 protesters gathered outside the assembly to voice their opposition to the agreement because they fear it enables the Serb minority to carve out a portion of Kosovo territory and join Serbia.
Kosovo lawmakers still will have to ratify any final agreement that will contain details about how it is implemented.
Serbia's government and parliament have yet to endorse the deal that came after months of tense negotiations between the two premiers.
Leaders of the two main ruling parties in Serbia said Sunday they will support the tentative agreement at a government session scheduled for Monday. A Serbian parliamentary session to discuss the issue will be held later in the week.
The agreement has triggered outrage among Serb nationalists who have scheduled major street protests. Several hundred far-right protesters marched in Belgrade on Sunday chanting "treason, treason" and demanding the ouster of the government.
Serbian Progressive Party leader and deputy Prime Minister Aleksandar Vucic said he did not rule out that a referendum could be held on the proposed deal, if a national consensus is not reached on how Serbia should deal with Kosovo.
The agreement would allow Serbs to police and manage the north of Kosovo, which is inhabited predominantly by ethnic Serbs, in exchange for nominal recognition of the authority of the Kosovo government. It also calls for the two sides not to obstruct one another as they seek eventual membership in the EU.
Serbia relinquished control of most of Kosovo in 1999 when NATO chased its troops out of the region after a three-month bombing campaign. Ending the partition of Kosovo between the Albanian majority and the Serb-controlled north—about a fifth of the country—is a key condition of Serbia's further progress toward EU membership.
Details about how the deal would be implemented on the ground remain murky especially since Kosovo Serbs have said they will not accept any authority coming from Pristina's ethnic Albanians.
Associated Press Writer Nebi Qena contributed to this report from Pristina, Kosovo.