South Korea has sent 17.8 billion won ($16.7 million) in humanitarian aid to North Korea in 2013, a 26 percent increase from last year, despite the spike in cross-border tensions, the Seoul government said Sunday.

In a report released by the Ministry of Unification, the total amount of aid sent to the communist country, including money donated to international organizations, represents a 26 percent increase from 14.1 billion won offered in 2012.

"Despite criticisms that Seoul has not done enough to help the disadvantaged in the North, the incumbent Park Geun-hye administration has sent more aid to Pyongyang than what was shipped last year when President Lee Myung-bak was in office," a government official said.

The official, who did not wish to be identified, pointed out that while critics have said the amount is small, people have to take into account the overall aid offered. North conducted its third nuclear test in February and threatened pre-emptive strikes against Seoul and Washington, seriously souring cross-border ties.

Fifteen local charity groups including the Eugene Bell Foundation and Korea Sharing Net provided 4.3 billion won, or a little over 24.1 percent of all aid to the North, with the rest coming from the South Korean government.

Seoul donated 13.5 billion won to the World Health Organization and the United Nations Children's Fund since President Park took office in late February.

Moving forward, the official said South Korea has no plans to provide direct food aid to the North but that it may consider offering matching funds to private charity organizations wanting to help the North.

The source said while Seoul has no plans to ease its so-called May 24 sanctions that ban all nonhumanitarian economic and social exchanges with the North, it has exercised flexibility and permitted limited cross-border contacts and transactions.

Seoul implemented the ban after it accused the North of sinking one of its warships in the seas off their west coast in 2010. The incident claimed the lives of 46 South Korean sailors.

"The policy of flexibility existed in the past and is nothing new," he said.

Meanwhile, on the government's plan to allow a South Korean consortium to invest in the Russian-led Rajin-Khasan rail and port development project in North Korea, the working-level official said it is an indirect investment.

"At present, there are no tangible details on how the consortium will get involved in the projects," he said.

He speculated that depending on how the final agreement is reached between interested parties, the plan may not conflict with the sanctions.

If headway is made on the deal signed on the sidelines of the South Korea-Russia summit in Seoul last week, South Korean companies could use the railway line in the North Korean port to ship goods to Russia and as far as Europe.

The state-run Russian Railways has a 70 percent stake in the joint venture, with the North holding the rest. South Korean companies are expected to buy part of the Russian stakes. (Yonhap News)