Venezuelan President Nicolas Maduro, whose nearly 12 years in office have been marked by a deep economic and social crisis, was sworn in for a third term on Friday, staying in power despite a six-month dispute over an election and international calls for him to stand aside.

President-elect Donald Trump says Venezuela's embattled opposition leader must be protected as President Nicolas Maduro takes the oath of office for a third six-year term.

Nicolás Maduro took the oath before parliament, vowing his third six-year term in office would be a "period of peace".