"WORLD WAR III," Trump wrote on his account on Sunday, without elaborating.
Trump has repeatedly accused US President Joe Biden of bringing the world to the "brink of World War III," saying that the situation would have been different if he were president.
In January, Trump said the world has become "more dangerous" under President Joe Biden and that the nuclear rhetoric was not employed against the US under his administration, but that foreign adversaries are using it now because they lack respect for the present US leadership.
Since Biden has taken office, tension have undoubtedly risen between the US and the world's other two major nuclear powers, China and Russia.