Timeline: Syria uprising enters a second year

March 15, 2011 About 40 people join a Syrian protest chanting political slogans in a brief first challenge to the Baath Party in Old Damascus before dispersing into side streets.

March 16 Security forces break up gathering in Damascus of 150 protesters holding pictures of imprisoned relatives.

March 18 Security forces kill three protesters in Deraa

April 19 Government passes bill lifting 48 years of emergency rule.

April 22 Security forces and gunmen loyal to President Bashar Al Assad kill at least 100 protesters, rights group says.

July 31 Syrian tanks storm Hama after a month-long siege.

September 2 EU imposes ban on purchases of Syrian oil.

November 12 Arab League suspends Syria.

November 27 Arab states vote to impose economic sanctions.

November 30 Turkey says it has suspended all financial credit dealings with Syria and frozen Syrian government assets.

December 7 Mr Al Assad denies ordering his troops to kill peaceful demonstrators, saying only a "crazy" leader kills his own people.

December 19 Syria signs Arab League peace plan, agrees to let monitors into the country.

January 22, 2012 Arab League urges Mr Al Assad to step down and hand over power to a deputy, a call Syria rejects a day later. Saudi Arabia quits monitoring mission, saying Syria has done nothing to implement Arab peace plan.

January 24 The GCC says it is withdrawing its 55 monitors from the 165-strong monitoring mission. Syria agrees to extend mission for a month. Four days later the Arab League suspends the monitoring mission.

January 31 Government forces reassert control over capital's eastern suburbs after Free Syrian Army withdraws, capping three days of fighting that activists say killed at least 100 people.

February 4 Russia and China veto resolution in UN Security Council, backed by Arab League, calling for Mr Al Assad to step down.

February 7 The Russian foreign minister visits Damascus, says Mr Al Assad assured him he is committed to seeking an end to violence by all sides.

February 12 Arab League calls for a UN-Arab peacekeeping force and opening of "communication channels with the Syrian opposition".

February 16 The UN General Assembly approves a resolution endorsing the Arab League plan calling for Assad to step aside.

February 22 More than 80 people are killed in Homs. Hundreds of people have now been killed in daily bombardments of the city by Assad's besieging forces.

February 23 The former UN secretary general Kofi Annan is appointed UN-Arab League envoy to Syria.

February 24 Foreign ministers from more than 50 countries meet in Tunis for the inaugural "Friends of Syria" meeting. Russia and China, allies of Syria, decide not to attend.

February 28 Mr Al Assad decrees that a new constitution is in force after officials say nearly 90 per cent of voters endorsed it in a February 26 referendum. Opponents and the West dismiss the reforms and the referendum as a sham.

March 1 Russia and China join other UN Security Council members in expressing "deep disappointment" at Syria's failure to allow the UN humanitarian aid chief, Valerie Amos, to visit. Syrian rebels pull out of the besieged Baba Amr district of Homs after more than three weeks of bombardment.

March 4 China warns other powers not to use humanitarian aid for Syria to "interfere" in Syria, while urging unity in the Security Council after a split with western powers.

March 6 The five permanent Security Council members and Morocco meet to discuss a US-drafted resolution urging an end to the crackdown. Some western envoys say the text is too weak.

March 7 The Syrian deputy oil minister, Abdo Hussameldin, announces his defection on YouTube, becoming the first high-ranking civilian official to abandon the regime.

March 9 Ms Amos, talks, a day after her visit to Homs, of her shock at what she had seen in the Baba Amr neighbourhood, and says the government agreed to a limited assessment exercise by UN agencies. The United Nations estimates at least 30,000 refugees have fled the fighting in Syria since the start of the conflict

March 11 Kofi Annan ends talks with Mr Al Assad and leaves Syria with little sign of progress. Assad tells Annan that opposition "terrorists" are blocking any political solution.

March 12 The United States and its European allies clash with Russia at a Security Council meeting over how to end escalating violence.

March 13 Mr Al Assad sets parliamentary elections under his country's new constitution for May 7. Three prominent figures resign from the opposition SNC saying they have given up on trying to make the group a more effective player in the revolt. The UN says over 8,000 people have been killed in Syria.

March 14 Kofi Annan says he has received a reply from Damascus to his peace proposals but he needs clarifications.