SEOUL, South Korea – North Korea agreed today to lift border restrictions with South Korea to allow reunions of separated families and restart stalled tourism ventures in its latest gesture of conciliation toward Seoul after nearly 18 months of rising tensions.

The North, however, said in a separate statement it was putting its army on “special alert” because of South Korea’s joint military drills with the United States this week, a sign that tension between the rival countries is still running high.

The North’s official Korean Central News Agency said in a dispatch this morning that it agreed to restart tours to the scenic Diamond Mountain resort and ancient sights in Kaesong in the North. The tours had been suspended in tensions after the inauguration of a conservative government in Seoul early last year.

The report did not say when the tours would resume.

The state news agency said the North also agreed to resume reunions of families separated by one of the world’s most heavily fortified borders at Diamond Mountain before this year’s annual “Chuseok” autumn harvest holiday in early October. Chuseok is one of the two biggest Korean traditional holidays celebrated in both Koreas and is equivalent to Thanksgiving in the United States.

The agreement was seen as a conciliatory gesture toward Seoul and Washington amid the standoff over its nuclear weapons program.