RIGA, Latvia -- Latvia's prime minister resigned Wednesday in the wake of supermarket collapse that killed 54 people and provoked outrage among the Baltic country's citizens.

Valdis Dombrovskis' unexpected announcement, which automatically triggers the fall of the entire centre-right government, followed his meeting with President Andris Berzins.

"Considering the ... tragedy and all the related circumstances, the country needs a government that has a majority support in parliament and can solve the situation that has arisen in the country," Dombrovskis told journalists after meeting the president.

Police have opened a criminal investigation into the cause of last week's tragedy. Possible explanations for the disaster include a flawed design, substandard construction materials, and corruption.

Some people have suggested that the abolition of a construction authority by Dombrovskis' budget-slashing government weakened oversight.

Many Latvians have expressed deep skepticism that the guilty parties will be bear criminal liability and have gone so far as to demand that foreign engineers be invited to help the investigation.

Dombrovskis, the country's longest-serving prime minister, denied that he was pressured by the president and said that he had been mulling such a move since last week's collapse of the Maxima supermarket, the worst disaster since Latvia declared its independence from Soviet Union in 1991.

Dombrovskis told journalists that country needed a new, broad-based coalition that would enjoy the trust of Latvia's 100-seat parliament.

President Berzins will appoint a new candidate based on who could form a coalition that will receive the necessary majority approval by parliament.

Dombrovskis came to power in 2009 as Latvia's economy was sinking into a deep recession and was charged with leading harsh budget cuts and tax increases while at the same time implementing tough structural reforms demanded by international organizations such as the International Monetary Fund.

Dombrovskis was re-appointed twice as prime minister since then, and is widely credited with preventing the small Baltic nation from going bankrupt.

Latvia's economy has returned to growth and was the fastest-growing in the European Union over the past two years.

On Jan. 1, Latvia will become the 18th member of the euro area.