SYDNEY (Reuters) - A senior U.S. state department official urged Papua New Guinea(PNG) to turn down China's offer of a potential security pact, warning the Pacific nation that any security guarantee with Beijing comes with consequences and costs.

"We've seen that the Chinese commitment in defence or investment comes with a high cost. That's what we'd say to PNG," United States Deputy Secretary of State Richard Verma told the Sydney Morning Herald in an interview published on Monday.

Papua New Guinea Foreign Minister Justin Tkachenko told Reuters last week that it was in early talks with China on a potential security deal. China has offered to assist PNG's police force with training, equipment and surveillance technology, Tkachenko said.

The U.S. and ally Australia for decades have seen the Pacific as their sphere of influence, and are seeking to deter the island nations from forming security ties with China, after Beijing signed a security pact with Solomon Islands in 2022.

Verma, in Australia last week after visiting the South Pacific, said it was a competition for influence in the resource-rich region, and that "we have to compete aggressively".

His comments came ahead of an address by PNG Prime Minister James Marape to the Australian parliament later this week. PNG has previously said Australia and the U.S. were its security partners, while China was an important economic partner.

"We would like to see people choose security arrangement or investment opportunities or advanced connectivity with countries that play by the rules, that live up to the international standards," Verma said.

"China has shown that it is not doing that. China has shown that it's not interested in the modern rules-based order."

He warned about the "false promise of authoritarian regimes" and said countries in investment arrangements with China have found that it can be a "debt trap".

"There are other options out there," Verma said.