The United States said Tuesday it has suspended more assistance to Thailand in response to a military coup and was considering moving a major regional exercise out of the kingdom.

Washington has blocked $4.7 million in security-related aid to Thailand, which accounts for roughly half of its $10.5 million in annual assistance to the longtime ally, State Department official Scot Marciel said in testimony to Congress.

The United States swiftly rebuked Thailand's military after it defied warnings not to intervene in the political chaos. The State Department announced that it had frozen $3.5 million in aid just one day after the May 22 coup.

The additionally suspended assistance has included a US-sponsored firearms training program for the Thai police and a study trip to the United States for senior Thai police officers, another US official said.

Marciel said that the United States was also considering moving next year's Cobra Gold -- one of the largest US military exercises and a key element in the US strategy of pivoting power to Asia.

The United States and Thailand have held the annual exercises together since 1980, this year involving some 13,000 participants from US-friendly nations across the region.

"We'll certainly be looking at it very closely. It will depend partly on what happens on the ground there," Marciel said in response to a question.

Representative Steve Chabot, the chair of the House Foreign Affairs subcommittee on Asia, said that exercises in Thailand "could clearly send the wrong message" to Thailand and around the world "in light of the repressive nature" of the junta.

Chabot called on President Barack Obama's administration to study moving the 2015 exercises, generally held early each year, to Darwin, Australia, where some 2,500 US Marines are deploying as part of the pivot to Asia.

- 'Clear' support for democracy -

Thailand has been in turmoil since 2006 when the military overthrew elected prime minister Thaksin Shinawatra, a billionaire turned populist champion of the poor who has shaken Bangkok's royalist elite and its allies in the army.

The military has clamped down harder with the latest coup. Army chief Prayut Chan-O-Cha has suspended the constitution, assumed sweeping powers and smothered dissent.

While some supporters of the royalist "Yellow Shirt" protest movement have called for changes to dilute the role of elections, Marciel said he believed that Thais broadly supported democracy.

If Thailand does not restore freedoms and allow elections, "over time there will be more and more Thai people who will look for opportunities to express their unhappiness," Marciel said.

"Can't really put a timeframe on it, but I do think the majority of Thai people have made clear they want democracy and certainly that's our view as well," he said.

Marciel downplayed lawmakers' fears that China -- which unlike Western nations and Thailand's neighbors has not criticized the coup -- would seize on the US shunning of the kingdom, saying that the crisis was rooted in domestic factors.

"I don't think there's any outside power that has undue influence in Thailand, including us or China," Marciel said.

The firm line on Thailand contrasts sharply with the US approach to Egypt.

Washington carefully avoided calling last year's ouster of elected Islamist president Mohamed Morsi a coup and said last week it had unfrozen $572 million in military aid after ex-army chief Abdel Fattah al-Sisi won an election.