Around the world, patience ran out with Syria's President Assad. Ambassadors and diplomats were expelled from embassies, including in the UK
A look at what countries have expelled Syrian diplomats in the wake of the Houla massacre
Countries from Australia to the UK have expelled Syrian diplomats in a coordinated move to step up pressure against the regime.
UN investigators say forces loyal to the Syrian government "may have been responsible" for many deaths in the Houla massacre but a full inquiry is needed.
Swedish foreign minister Carl Bildt has said that he believes the EU should maintain a "common approach" towards Syria.
Why have those that closed their embassies in Syria let Syrian ones in their countries remain open? We still have our eyes and ears there.
And we have argued that EU should have a common approach on these issues. That's how we can be effective.
The Syrian ambassador in Switzerland, who is also the Syrian envoy to France, has been expelled.
Bulgaria is expelling Syria's Charge d'Affaires as part of an international response to the massacre of civilians in the Syrian village of Houla, its Foreign Ministry said on Tuesday.
In a statement the ministry said:
Salah Soukkar will be informed today that he has to leave Bulgaria in the next 72 hours
Two other diplomats at the Syrian embassy will also be expelled and Bulgarian mission will temporarily close in Damascus and its diplomats will return.
The United States has confirmed that it has expelled the Syrian Charge d'Affaires. The State Department has issued the following statement:
In response to the May 25 massacre in the village of Haoula, today the United States has decided to expel Syrian Charge d'Affaires Zuheir Jabbour from the country. We took this action in coordination with partner countries including Australia, Canada, Spain, the United Kingdom, Italy, France, and Germany.
United Nations observers confirmed the deaths of more than 90 people, including at least 30 children under the age of 10, after the vicious assault involving tanks and artillery - weapons that only the regime possesses. There are also reports that many families were summarily executed in their homes by regime forces.
We hold the Syrian government responsible for this slaughter of innocent lives. This massacre is the most unambiguous indictment to date of the Syrian government's flagrant violations of its UN Security Council obligations under Resolutions 2042 and 2043.
We encourage all countries to condemn the actions of the Assad regime through similar action.
The Netherlands has become the latest country to expel its Syrian ambassador.
Foreign Ministry sources in Italy have confirmed that the Syrian ambassador will be expelled, in line with a number of other countries - Reuters