When Kenya's opposition leader Raila Odinga speaks to supporters Tuesday, his words have the power to ease or deepen the crisis triggered by his rejection of last week's election result.

The 72-year-old insists he is the rightful winner of a "stolen" election that handed victory to incumbent President Uhuru Kenyatta.

But after days of sometimes violent protests and several deaths following the announcement of results late Friday, life showed signs of returning to normal across the country on Monday.

Odinga has lost three previous elections and has claimed he was cheated of victory in the last two.

After the 2007 vote his supporters took to the streets during months of politically motivated tribal violence that left over 1,100 dead. Finally, an internationally brokered compromise led to a coalition government in which Odinga served as prime minister.

In 2013 he challenged the presidential results in court, and lost. But this time, Odinga has so far defied pressure to take his complaints to the court.

On Sunday he told cheering supporters, "We are not done yet. We will not give up. Wait for the next course of action" -- and promised to speak again on Tuesday.

But after nearly a week in which businesses stayed shut and workers stayed home, the capital Nairobi came back to life on Monday, with many unable to afford more time away from their jobs.

"I came to work because I need to eat, I need my children to eat, and I need my grandchildren to eat," said Margaret, 62, a hairdresser in the Kibera slum, an Odinga stronghold.

"They can call us to strike, but at the end of the day, they'll be eating and we won't," she added.

"You know, I am very sad that Raila did not win, but what can he do now? It's over and we want peace."

- 'The election is over' -

Speaking Monday, Kenyatta tried to draw a line under the election and its aftermath. "Kenyans have said that the election is behind them, the majority have returned to work," he said.

He also reached out to Odinga, offering a "hand of peace" and urging him to use legal means to express his grievances, including peaceful demonstrations if he chose not to go to court.

"Just do it peacefully, orderly... As a government we will not allow loss of life, destruction of property and looting, because many, many millions of Kenyans also are desirous to go about their business as before," he said.

At least 16 people have been killed since Friday night, according to an AFP tally, including a nine-year-old girl hit by a stray bullet.

Police have denied innocent protesters have been killed, saying those shot dead had been armed and attacked officers, many while carrying out criminal acts such as rape and looting.

The dispute has plunged Kenya into its worst political crisis since the 2007 post-election violence that laid bare decades-old political and ethnic grievances over access to power and land.

Three of Kenya's four presidents -- including Kenyatta and his father -- have been Kikuyu. The other was Kalenjin.

That leaves Luos, Odinga prominent among them, and other major ethnic groups feeling excluded from power and marginalised for over half a century.

The ethnic nature of Kenya's politics and the deep resentment it breeds, means Kenya is on tenterhooks as it waits to see what Odinga's next move will be.

"I will do whatever he asks," said one supporter, 50-year-old Polycarp Orinda, in the Kibera district of the capital. "I will go to the streets if he wants us to go there."

Source: AFP