US President Donald Trump has responded to a deadly train derailment in Washington State by promoting his latest policy priority: infrastructure.

"The train accident that just occurred in DuPont, WA shows more than ever why our soon to be submitted infrastructure plan must be approved quickly," Mr Trump tweeted.

He also lamented the amount of money his country had spent building infrastructure in the Middle East, adding: "Seven trillion dollars spent in the Middle East while our roads, bridges, tunnels, railways (and more) crumble! Not for long!"

It was unclear from where Mr Trump took the $7 trillion figure. The latest estimates from Harvard and Brown universities put the cost of American wars in Iraq, Afghanistan, Syria and Pakistan at between $3 trillion and $6 trillion.

An Amtrak train derailed on an overpass near DuPont on Monday morning, killing at least six people and wounding dozens more. Washington Governor Jay Inslee declared a state of emergency in two counties affected by the derailment, according to CNN.

Mr Trump followed up his initial tweet with one thanking first responders and offering his thoughts and prayers to everyone involved in the accident. He added that he was monitoring the situation from the White House.

Monday was the first day that Amtrak trains outside of Seattle were set to run along new lines, which were previously only used by regional commuter rail services. The rerouting was part of a plan to bring high-speed trains to the area.

Mr Trump has used disasters to promote his policy agenda in the past. In September, Mr Trump suggested that a terrorist attack in London evidenced the need for his ban on travellers from six Muslim-majority countries.

“Another attack in London by a loser terrorist,” the President tweeted at the time. “The travel ban into the United States should be far larger, tougher and more specific – but stupidly, that would not be politically correct!”

Mr Trump is poised to unveil his latest policy priority – a $1 trillion infrastructure plan – after Congress passes the Republican tax reform bill. According to Politico, however, some Democrats are already organising to fight the plan, which would cost the federal government some $200bn over the next decade.

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