Portugal's government is about to be ousted by a coalition that includes two of Europe's most left-wing parties

Portugal communist red flag hammer sickle(AP Photo/ Francisco Seco)Portuguese communists take part in a demonstration against economic austerity measures taken by Portugal’s Socialist government, on Wednesday, June 17, 2010 in downtown Lisbon.

Portugal’s centre-right government looks likely to be ejected from office on Tuesday evening, only a month after the country’s most recent parliamentary election.

A vote of no confidence from the country’s parliament is expected to send Prime Minister Pedro Passos Coelho packing, with a left-wing coalition waiting in the wings.

The two centre-right parties which formed a coalition after the 2011 election ran under a “Portugal Ahead” banner in 2015 vote, winning 38.6% of the vote and 106 of the parliament’s 230 seats.

In October, it was generally reported as a victory for the centre-right movements, and presumed that they would return to government. Though they had lost their majority, they overturned a long-term polling lead for the mainstream centre-left Socialist Party (PS), led by Antonio Costa.

Since then, it’s become clear that there’s a possibility of a coalition among the divided left.

The “triple left” alliance includes the Socialist Party, the Left Bloc, and the Communists. Though all parties are categorised on the progressive end of the political spectrum, there are major divisions, too.

On a left-right economic spectrum, there are very few parties more to the left than the Left Bloc or Communists, according to the European Union Centres of Excellence at Chapel Hill, North Carolina.

Of the 268 EU political parties that they assess, the Left Bloc is the 8th-most left-wing party and the Communists are the 4th-most left-wing. PS is the 122nd-most left-wing, pretty close to the middle of the distribution.

To put that in perspective, Syriza, the radical coalition that won Greece’s election and orchestrated a six-month standoff with Europe’s governing institution comes only 22nd. That’s based on a 2014 survey before the party split from its hard-left flank this year.

The Communist party and Left Bloc are also by some distance the country’s most eurosceptic parties, coming 25th and 59th for opposition to EU integration on the same survey of 268 organisations. PS, on the other hand, comes 205th, making it much more obviously pro-EU.

Demands from the two harder-left parties include bringing back four recently abolished bank holidays and the general reversal of many austerity policies introduced in recent years.

The likelihood of the new government taking over has sent Portugal’s 10-year government bond yields climbing. Bond yields are a common measure of the risk associated with holding a country’s debt, with higher yields meaning greater returns for more elevated risk.

The 10-year yields are now back to levels last seen during the summer’s bund tantrum:

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