“Mentally deranged”, “bereft of reason” and a “madman on the loose” – these are the things two world leaders have been saying to each other in 2017.

They are US President Donald Trump and North Korea’s Supreme Leader Kim Jong-un

There have been six nuclear tests by North Korea in 2017, with the last one just a few days ago.

The most extreme insults began flying between the pair in April.

Trump said: “We have a lot of firepower, more than he has, times 20 – but we don’t want to use it,” he added.

In May, three missile tests took place and one was intercepted by the US near the Pacific Ocean.

Trump responded on Twitter, obviously.

Things really picked up from July onwards as North Korea got verbal too.

On the 4 July, US Independence Day, the country launched its most powerful missile yet, an intercontinental ballistic missile, which they said was capable of “hitting anywhere in the world”.

The state-run North Korean news agency then quoted Kim Jong-un as saying “the American ******** would not be very happy with this gift sent on the July 4 anniversary”.

It all appeared to calm down for a few weeks until there was another missile launch at the end of July.

This week has again seen the two leaders locked in even more angry verbal battle.

“If the righteous many do not confront the wicked few, then evil will triumph, the US has great strength and patience,” Trump said in an address to the United Nations on Tuesday.

“If forced to defend ourselves or our allies, we will have no choice but to totally destroy North Korea.”

Kim Jong-un responded via North Korea’s state media.

“I will surely and definitely tame the mentally deranged US dotard with fire,” he said. “Dotard” is an insult, meaning old or weak.

And Trump, not satisfied with his previous warnings to North Korea, tweeted a message on Friday morning, using the recurring phrase “madman”.

Meantime, some powerful US bombers and fighter escorts flew off the coast of North Korea on Saturday in a show of force.

The power show is against North Korea’s nuclear weapons programme and intransigence, but the action is escalating already sky-high tensions in the region.

The hermit state’s foreign minister meanwhile derided Donald Trump as “mentally deranged” at the United Nations, while the US president fired back on Twitter with fresh threats.

The latest exchange of bellicose rhetoric comes as international alarm mounts over Pyongyang’s weapons ambitions — including a suggestion this week that the country is considering detonating an H-bomb over the Pacific.

US bombers have carried out similar flights before, as the United States and the international community struggle to rein in North Korea’s weapons programmes.

But in a new stage for such show-of-force operations, the Pentagon stressed this was the furthest north of the Demilitarized Zone (DMZ) between the two Koreas that any US fighter or bomber has flown off North Korea’s coast in this century.

“This mission is a demonstration of US resolve and a clear message that the president has many military options to defeat any threat,” Pentagon spokeswoman Dana White said.

“We are prepared to use the full range of military capabilities to defend the US homeland and our allies.”

The Air Force B-1B Lancer bombers flown Saturday are based in Guam, and were accompanied by F-15C Eagle fighter escorts from Okinawa, Japan, White said. They flew over international waters off the east coast of North Korea.

There was another reason for concern after an underground rumble near North Korea’s nuclear test site. China at first said it suspected an explosion.

But it was later ruled by a nuclear test ban watchdog and other experts to be a shallow 3.5-magnitude earthquake and likely an aftershock from the hermit state’s latest nuclear test on September 3. Agency Reports