Portugal's prime minister proposed on Wednesday a confidence vote in his year-old minority government, risking his own dismissal as the main opposition parties vowed to defeat him.

LISBON (Reuters) - Portugal's cabinet has decided to go ahead with a motion of confidence in the centre-right government that is opposed by the main opposition parties, it said on Thursday, with a parliamentary vote expected to take place next Tuesday.

Portuguese Prime Minister Luis Montenegro said he plans to seek a confidence vote in a parliament where he only has minority backing, after struggling to put an end to speculation about potential conflicts of interest related to a company owned by his family.