SEOUL - An international rights group urged US President Barack Obama to take a strong stance on North Korea's human rights abuses during his visit to South Korea starting late Wednesday.

"North Korea’s nuclear ambitions have overwhelmed all other issues for too long," said Elaine Pearson, deputy Asia director at Human Rights Watch.

Obama meets President Lee Myung-Bak Thursday for talks expected to focus on the North's nuclear program and a stalled US-South Korean free trade pact.

Human Rights Watch said in a statement the leaders "should make a public commitment to address human rights concerns in North Korea as well as the plight of North Korean refugees."

Their discussions should cover public executions, detention abuses, the punishment of North Koreans who are repatriated from China and workers’ rights, the New York-based watchdog said.

It said Obama and Lee should press China to stop arresting and repatriating North Korean refugees and instead offer them protection and shelter in line with its international obligations.

China repatriates the refugees as economic migrants, even though they can face harsh punishment back home.

Robert King, the nominee for US envoy on human rights in North Korea, said this month he would press China to treat them better.

Almost 17,000 North Koreans have arrived in South Korea since the end of the 1950-53 Korean War. The vast majority fled first to China and then traveled on to Southeast Asian nations before flying to Seoul.

Human Rights Watch also noted that fewer than 100 North Korean refugees had resettled in the United States in the past five years.

"The US needs to speed up refugee screening and send its embassies clear instructions on how to help them," Pearson said.

The watchdog also called for basic labor rights for 40,000 North Koreans working in South Korean factories at the Kaesong joint industrial estate in the North.

It said the free trade pact, which awaits ratification by legislatures in both countries, raises the possibility that Kaesong-made goods could enter the United States duty-free.

Human Rights Watch said Obama should make it clear that this would depend on better conditions for workers there in line with international standards.

An expert told the United Nations last month that the North's rights record remains "abysmal" and more than one-third of its people go hungry.

"The freedoms from want, from fear, from discrimination, from persecution and from exploitation are regrettably transgressed with impunity by those authorities, in an astonishing setting of abuse after abuse," said Vitit Muntarbhorn, UN special reporter on human rights in the North.