An opposition leader in Armenia has been arrested and accused of preparing to kill the prime minister, his lawyer said, adding to the political turmoil created by a controversial peace deal with neighbouring Azerbaijan.

Thousands of Armenian demonstrators, chanting "Nikol is a traitor", demanded Prime Minister Nikol Pashinyan resign on Wednesday over a ceasefire that secured territorial advances for Azerbaijan in Nagorno-Karabakh after six weeks of fighting.

Armenian Prime Minister Nikol Pashinyan, who turned 45 on Monday, said he and his family had tested positive for the new coronavirus and that he would be working from home.

New Armenian Prime Minister Nikol Pashinyan, who was swept to power this week on the back of popular protests, said on Thursday he had sacked the heads of the country's police and security service.

The Qatar Stock Exchange (QSE) index decreased by 185.58 points, or 1.64%, during the week to close at 11,134.81.