Oil climbs on US-Iran deadlock

Oil prices climbed on Tuesday as US-Iran talks stalled, while South Korean calls for a social tax on AI profits dragged down the tech-rich Kospi index.

Seoul plunged five percent after a top official proposed a "national dividend" to redistribute excess corporate profits from artificial intelligence.

South Korea is riding an AI chip boom driving massive earnings for tech giants Samsung and SK hynix and sending the Kospi to record highs in recent weeks.

In Southeast Asia's biggest economy Indonesia, Jakarta was also down, falling two percent after the rupiah hit a record low against the dollar.

The burst of activity in Seoul and Jakarta contrasted with subdued markets elsewhere, with traders sitting on the sidelines amid uncertainty over the Middle East war.

Hong Kong, Shanghai, Sydney, Bangkok, Manila and Singapore were marginally lower, while Taipei and Kuala Lumpur were up.

Tokyo closed 0.5 percent higher after Finance Minister Satsuki Katayama said Tokyo and Washington were "coordinating very well" on currency policy during US Treasury Secretary Scott Bessent's visit.

Weekend optimism over Washington's proposal to Iran to ease the conflict collapsed when US President Donald Trump told reporters on Monday that Tehran's counter-offer was "garbage".

Trump warned that Iran's rejection of his administration's demands meant the already tenuous ceasefire is now "unbelievably weak".

The impasse, which leaves the vital Strait of Hormuz mostly closed to oil tanker traffic, unnerved global energy markets.

The international benchmark Brent crude jumped 1.3 percent to $105 a barrel, while US benchmark West Texas Intermediate rose 1.6 percent to $99 a barrel.