The Zimbabwean president used his inauguration speech to slam gays and critics of his country's politics.

JOHANNESBURG - Zimbabwean President Robert Mugabe used his inauguration speech on Thursday to lash out at homosexuality as well as the west's scepticism of his country's electoral process.

The 89-year-old was sworn in for a seventh term as Zimbabwe's leader in Harare, extending his 33-year rule.

In the speech, Mugabe urged young people to "damn" homosexuality in the same way his government does and not to offend nature by engaging in same-sex relationships.

"That destroys nations, apart from it being a filthy, filthy disease," he said.

Ahead of the elections last month, Mugabe heightened his anti-gay stance in his rallies, going so far as to suggest that homosexuals should be castrated.

Previously, Mugabe once controversially described homosexuals as worse than pigs and dogs, saying, if he had his way, gay people would go to hell and rot.

At the National Sports Stadium on Thursday, where around 30 former and currently serving heads of states were in attendance, the president also used the opportunity to slam critics in the west who questioned the elections in Zimbabwe last month, calling them "vile".

"Foreigners, please keep out of our problem; we will solve those problems ourselves."

The crowd erupted into cheers and shouts and dancing as Chief Justice Godfrey Chidyausiku put the green sash of office over the president's head.

The 89-year-old leader then swore to be faithful to Zimbabwe and to obey and uphold the nation's constitution.

Chidyausiku is the same judge who dismissed Tsvangirai's election challenge in the Constitutional Court earlier this week.