THE Democratic victory in the US House of Representatives could echo from Moscow to Beijing to Riyadh, with empowered Democrats now able to launch new investigations into President Donald Trump’s international business empire and his political dealings with the rest of the world.

Overturning control of the House in Tuesday’s midterm elections has given the Democrats a powerful weapon to wield against Mr Trump: the subpoena.

The Democratic leaders of many House committees will have subpoena powers enabling them to obtain documents, emails and testimony.

That means Democrats could look into such issues as the 18 trademarks that China has granted in recent months to companies linked to Mr Trump and his daughter Ivanka, and whether they reflect conflicts of interest.

China says it handles all trademark applications equally, but House committees could probe whether Beijing can exploit the Trump family’s substantial intellectual property holdings in China for political or diplomatic advantage.

On Wednesday, Chinese foreign ministry spokeswoman Hua Chunying would not comment directly on the election results, saying she didn’t want to be accused of interfering in the election.

For Moscow, the Democratic victory means a probable reopening of the investigation into Russian interference in the 2016 election.

The Republican-led Intelligence Committee closed its probe into Russian meddling, saying it had found no evidence of collusion between Russia and the Trump campaign.

Democrats, though, have long said the Republicans ignored a string of key facts and witnesses.

Russian President Vladimir Putin denies any involvement in Mr Trump’s election victory, but he may quietly favour renewed investigations, seeing them as a way to sow chaos and division in America’s bitterly divided political arena.

What he would not favour, though, would be investigations or sanctions that damage the well-connected Russian oligarchs believed to have helped fund the meddling efforts.

Then there’s Saudi Arabia, and the relationship between Crown Prince Mohammed bin Salman and Mr Trump’s son-in-law, Jared Kushner.

The ties between the two men, who are said to communicate frequently, could come under increased scrutiny by Democrats.

The US and Saudi Arabia have long been key allies, and Mr Trump made the country his first stop abroad as president.

But the crown prince has lost supporters in Congress since the killing of Saudi writer Jamal Khashoggi, a Washington Post columnist and a critic of Prince Mohammed.

The fallout for Saudi Arabia could be immense, with Democrats possibly trying to block major arms sales to Saudi Arabia and curtail US support for Saudi Arabia’s war in Yemen, which the prince launched as defence minister in 2015.