ANURADHAPURA, SRI LANKA - Sri Lanka's new president and scourge of the Tamil Tigers Gotabaya Rajapaksa on Monday urged minorities unnerved by his election victory to work with him, as he was sworn in at a ceremony steeped in symbolism for his core supporters.

Having spearheaded the brutal end of the Tamil separatist war a decade ago, Rajapaksa is a divisive figure but popular among his own majority Sinhalese-Buddhist community.

His landslide win split the island nation of 21.6 million on religious and ethnic lines as never before, seven months after deadly Islamist attacks.

At the ceremony, Rajapaksa put his success down to the "extraordinary blessings of the Buddhist monks".

"The main message of the election is that it was the Sinhala majority vote that allowed me to win the presidency," the 70-year-old retired lieutenant colonel said.

"I knew that I could win with only the votes of the Sinhala majority. But I asked Tamils and Muslims to be a part of my success. Their response was not what I expected. However, I urge them to join me to build one Sri Lanka," he said.

Rajapaksa was defense chief under his brother Mahinda's 2005-15 presidency, when the military conducted a no-holds-barred campaign to end the 37-year war in which 100,000 people perished.

This makes the brothers heroes among Sri Lanka's Sinhalese majority and the powerful Buddhist clergy.

But around 40,000 Tamil civilians were allegedly killed in the closing stages of the conflict, which ended in 2009, and Saturday's election saw Tamils -- who account for about 15 percent of the population -- vote overwhelmingly against Rajapaksa.

As defense secretary Gotabaya had unfettered control over the security forces, while "death squads" that abducted dozens of dissidents, opponents, journalists and others also allegedly reported to him.

Many people were never found again after being bundled into feared white vans, while some were killed and dumped by roadsides.

The new president has denied any involvement and has resisted international calls to investigate the alleged war crimes.

At his only press conference during a three-month election campaign, Rajapaksa reiterated that he will not allow Sri Lankan troops to be tried by any war-crime tribunal, foreign or local.

He had also pledged to exonerate the dozens of military personnel accused of abductions, extortion and killings during his brother's decade in power. -AFP