U.S. Secretary of State Condoleezza Rice arrived Thursday in South Korea on a bid to press Seoul to support efforts to sanction North Korea for its nuclear test that rattled the world.

Rice's trip is part of a regional tour to rally support for a U.N. Security Council resolution with tough action by the countries who are the North's main trade partners. South Korea has previously been reluctant to inflame the North, maintaining its policy of reconciliation that has led to unprecedented cooperation between the former wartime foes.

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There were signs before Rice arrived, however, that Seoul's patience has run out.

South Korea's Yonhap news agency reported Thursday that Seoul has decided to halt subsidies to a joint tourism venture to the North's Diamond Mountain that has been operating since 1998. The report, which didn't cite any source, also said the South was planning to inspect cargo heading to North Korea, and also to inspect North Korean ships stopping at South Korean ports.

The South's Unification Ministry couldn't immediately confirm the report. It said the plans were being considered but no final decision had been made.

Washington had expressed skepticism about the tourism project earlier this week, with top U.S. nuclear envoy Christopher Hill saying in Seoul that the venture seemed to be "designed to give money to the North Korean authorities."

Yonhap also said South Korea was reconsidering how it pays workers at a joint economic zone in North Korea's border city of Kaesong. Officials were considering paying the laborers directly, rather than sending the money to a group account for later disbursement, which critics say is vulnerable to abuse.

Yonhap said the South also won't provide additional material or tools for projects to link rail lines and roads between the Koreas, which remain technically at war and are separated by the world's most fortified border.

Seoul was also considering whether to ban future shipments of emergency aid promised after the North suffered devastating floods in mid-July, Yonhap said. Seoul already halted regular aid after the North test-launched a barrage of missiles in early July over international objections.

Ties between Washington and Seoul were strained even before the test. The U.S. has called for a tougher line against Pyongyang, while South Korea has been reluctant to take moves that could inflame tensions -- following the "sunshine policy" of engagement it has pursued since a 2000 summit between the two nations' leaders.

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