Portugal’s third general election in three years has failed to deliver the result that could break the worst spell of political instability for decades in the European Union country of 10.6 million people.

By Sergio Goncalves, Catarina Demony and Andrei Khalip LISBON (Reuters) -Portugal's far-right Chega won a record vote share in Sunday's snap election and was vying to become the main opposition party as the ruling centre-right Democratic Alliance (AD) again fell short of a majority needed to end a long period of instability.

Portugal's governing right-of-centre Democratic Alliance has won snap parliamentary elections - the third in as many years - again falling short of a majority. Its leader Luís Montenegro promised supporters to "stimulate investment" and to "guarantee prosperity and social justice".