All 58 UPND lawmakers shunned the official opening of parliament and party secretary general Stephen Katuka
Zambia's main opposition party on Friday boycotted President Edgar Lungu's first parliamentary address since his contested re-election, which his rivals say was rigged.
The poll campaign saw clashes between supporters of Lungu's Patriotic Front (PF) and his rival Hakainde Hichilema's United Party for National Development (UPND).
All 58 UPND lawmakers shunned the official opening of parliament and party secretary general Stephen Katuka declined comment when approached by AFP.
Lungu, who won the August 11 election by around 100,000 votes, condemned the violence.
"Zambia has had a long record of peaceful elections -- it was disheartening to witness the post-election violence," he told parliament.
"I condemned the violence in the strong terms and I still condemn it."
Hichilema, a wealthy businessman who has run five times for president, accused Lungu, the election commission and court judges of fraud over the vote result.
With prices of copper, the country's key export, on a downward slope and unemployment and inflation soaring, Lungu said Zambia had to diversify its economy.
"We have to make agriculture a real business venture and our focus should be boosting agriculture production," he said.
Lungu also vowed to fight corruption, saying there would be "no sacred cows and sacrificial lambs".
Zambia, a British colony until 1964, recorded GDP growth of 3.6 percent last year -- its slowest rate since 1998.