Five Key Moments in Venezuela Crisis

Venezuela on Monday marks a month since the start of a wave of deadly protests against President Nicolas Maduro. 

Opponents started rallying on April 1 against moves to strengthen his hold on power, hoping they would be a tipping point in the economic and political crisis.

Here are five key steps that have led to this point:

- 2013: Chavez dies -The father of Venezuela's "socialist revolution," Hugo Chavez, a vocal critic of the United States, died of cancer on March 5, 2013.

His vice president, Nicolas Maduro, narrowly won the election to succeed him, beating center-right leader Henrique Capriles.

- 2014: Oil falls -Chavez had spent Venezuela's oil revenues on social welfare and vowed to defend the poor, winning the hearts of many.

But from mid-2014, world oil prices tumbled, slashing the country's revenues and imports and causing shortages of food and medicine.

- 2015: Opposition gains -As the economy worsened, the center right-led opposition won control of the legislature in elections in December 2015.

That set the stage for an intensifying political struggle as Maduro resisted lawmakers' efforts to legislate against him.

- 2016: Referendum fails -Maduro resisted opposition efforts to hold a referendum in time to remove him from power before the end of his term.

Vatican-backed negotiations also broke down with the sides accusing each other of bad faith.

- 2017: Protests swell -The Supreme Court seized power from the legislature in March but reversed the move after international outrage. The authorities later banned Capriles from politics. The moves prompted angry street protests that have killed at least 28 people.

"Key groups remain united around Maduro... but that unity is more fragile than in the past," analysts at the Eurasia Group consultancy wrote on April 20.

"Mounting pressures from both the streets and the international community have the potential to widen -- if not blow open entirely -- existing fissures."