Trump, 73, spent just over an hour on Saturday having "examinations, labs and discussions" at the Walter Reed National Military Medical Centre in Washington
A fifth man was hospitalised in a critical condition.
The US congressional committees leading the impeachment probe cranked up the heat on the White House this week.
Democrats have accused Trump of pressuring a vulnerable US ally to get dirt on a political rival for personal political gain.
Giuliani has emerged as a central figure in a scandal that has now engulfed Trump and left him facing an impeachment enquiry.
Despite the tremor's strength, there were no reports of injuries, impacts to basic services or damage to infrastructure, according to Chile's National Emergency Office.
Democrats with military and intelligence backgrounds described the impeachment investigation as a duty, not a political fight they relished.
Cattle farmers are already struggling to adjust to the terms of two major free trade deals inked by Japan in recent years.
Trump denied claims that he abused his office by repeatedly urging President Volodymyr Zelensky to probe his rival Joe Biden.
Mohammed, a Pakistan native thought to be about 54, is a key figure in the trial: he has been accused of being the mastermind of the 9/11 plot.
The White House said that Trump's statement about having some regrets over his trade war against China had been misunderstood as a softening of his position.
Trump pushed back against talk of a looming recession after a raft of US data reports last week gave a mixed outlook for the economy.
US officials have indicated that they believe an explosion in northern Russia last week may have been related to work on a nuclear-powered cruise missile.
The US had already slapped a 25 per cent tariff on a separate $250 billion of Chinese imports.
President Donald Trump described the gunman as a "wicked murderer"