No clear winner emerged in a nail-biting finish to Spain's election on Sunday as the right failed to fulfill predictions of a victory big enough to push Prime Minister Pedro Sanchez from power. The two leading parties will seek to negotiate coalition deals in pursuit of a governing majority but analysts warned the process could end in a hung parliament and another election.

With 100% of votes counted by 1:30 a.m. on Monday, the opposition center-right People's Party (PP) had 136 seats in parliament while Sanchez ruling Socialists (PSOE) had 122 seats.

Both were short of the 176 seats needed to govern. But the Socialists performed better than forecast while the PP failed to clinch a predicted clear majority, injecting drama into the vote counting.