UEFA has taken the unprecedented step of suspending the Champions League and Europa League following the coronavirus outbreak.

Barcelona against Napoli and Bayern Munich's clash with Chelsea were due to take place next week, but UEFA has now postponed competition. Manchester City vs. Real Madrid and Juventus' match with Lyon were already postponed before Friday's announcement.

Manchester United's second leg Europa League tie with LASK, due to be played on Thursday, also has been postponed, along with all other fixtures in the competition.

UEFA said in a statement: "In the light of developments due to the spread of COVID-19 in Europe and related decisions made by different governments, all UEFA club competitions matches scheduled next week are postponed.

"This includes the remaining UEFA Champions League round of 16 second leg matches scheduled on March 17 and 18, 2020; all UEFA Europa League round of 16 second leg matches scheduled on 19 March 2020; all UEFA Youth League, quarterfinal matches scheduled on March 17 and 18, 2020.

"Further decisions on when these matches take place will be communicated in due course."

UEFA will discuss the postponement of Euro 2020 during an emergency video conference involving all 55 European football associations on Tuesday.

Football matches across Europe have been severely affected, with La Liga suspending competition for two matchdays, Serie A suspended until April 3 and various postponements and matches played behind closed doors across European competitions before the postponement was put in place.

In the Champions League, Borussia Dortmund's match at Paris Saint-Germain took place behind closed doors on Wednesday, although many PSG fans congregated outside the Parc des Princes for the round-of-16 tie that the Ligue 1 side won 3-2 on aggregate.

In the Europa League, Sevilla vs. Roma and Inter Milan vs. Getafe were initially postponed amid the outbreak, while Manchester United's first-leg tie against LASK took place behind closed doors on Thursday before the move came to suspend competition completely.

- Coronavirus: Cancellations and reactions in sports
- Juventus defender Rugani tests positive for the coronavirus
- Mbappe tests negative for the coronavirus
- Man United back Prem suspension for the coronavirus

The decision comes across widespread disruption across European football. Real Madrid were placed into quarantine, which led to the suspension of La Liga, while Juventus' Daniele Rugani became the most high-profile footballer to be diagnosed with the virus.

Manchester City vs. Arsenal in the Premier League was called off, with a decision expected to be made soon regarding what happens in England's top division for the remainder of the season.

Elsewhere, CONMEBOL is asking FIFA to suspend the beginning of World Cup qualifiers scheduled for the end of March. They published on Wednesday a letter with the request to the sport's governing body in the name of members Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Paraguay, Peru, Uruguay and Venezuela. FIFA is yet to reply.

In other sports, the NBA has suspended its league.

Coronavirus, officially known as COVID-19, has surged around the world in recent months.

The coronaviruses are a family of viruses that cause illnesses ranging from the common cold to more serious respiratory diseases. Flu is caused by a different virus. There is no vaccine for coronavirus, though researchers are working on one and hope to begin testing soon.

Older people, especially those with chronic illnesses such as heart or lung disease, are most at risk. The coronavirus spreads mainly through coughs and sneezes, though it also can be transferred from surfaces.

The best way to prevent infection is by frequent hand-washing, cleaning surfaces with regular household sprays and wipes, and avoiding close contact with people who are sick.