The Greek referendum result is giving heart to anti-austerity parties in other countries.
Portugal's main opposition Socialist Party, which will bid for power in elections due in three months' time, says Greece's troubles show that a new approach is needed to the eurozone's financial difficulties.
Socialist leader Antonio Costa said austerity policies are "wrong" and endanger European unity. A new focus on growth is needed to rid the eurozone of the deep economic differences between its 19 members, he said.
Like Greece, Portugal got a bailout, when it asked for 78 billion ($86 billion) in 2011. Spending cuts and tax hikes have reduced its budget deficit but have increased unemployment and reduced living standards.
Portugal's center-right coalition government, which has staked its reputation on austerity policies to reduce the country's huge debt burden, made no comment.