US President Donald Trump says his newly renovated Lincoln Memorial reflecting pool in ‌Washington will “probably” have to be drained for repairs after “vandalism”.

“We met ‌with contractors today, will probably be forced to release and drain much of the water in order to do the necessary repairs, but will have them done as quickly as possible,” Trump wrote in a post on the social media website ‌Truth Social.

Several alleged ‌vandals have ⁠been arrested, according to Trump.

It follows Trump’s much-heralded $20 million renovation of the Washington landmark to turn it “American flag blue”. Water in the pool began turning green just a week after work was declared finished.

Hydrogen peroxide dumped in it last week to try to stave off the colour change brought on by a rapid algal bloom. It didn’t work.

In addition, the pool’s new “American flag blue” surface is peeling off in chunks.

“Many additional people have been ​arrested having to do with the disgraceful Vandalism of our beautiful Reflecting Pool,” Trump wrote on Sunday (local time).

One of those arrested was David Hearn, 67, who owns a company that makes composite used to build watercraft. A former US Olympic canoeist, said he stopped by the pool during a bike ride on Friday (local time) to see what all the fuss was about.

Hearn told The Associated Press that he wanted to examine the peeling new coating. He said he briefly touched a piece that was still attached to the side of the pool, then let go shortly after a park worker told him to.

Hearn said he was then detained by National Guard troops and Park Police for five hours before being released late on Friday.

“I’m a curious citizen,” Hearn said in a telephone interview.

“I reached down to see what it felt like. It was very rubbery.”

Trump did not provide evidence to support his allegation of vandalism, which he said included someone pouring corrosive chemicals into the pool.

In posts on Truth Social, he accused unnamed “Radical Left Lunatics” of damaging the base lining and even singled out on TV journalist for allegedly pulling at it.

“Lightweight ABC Reporter, Jonathan Karl, was seen sticking his hand into the Pool, and trying to rip the rubber off of the surface. The algae is 75 per cent gone, and the condition will soon be completely remedied, and the area that was vandalised, fortunately, is just a small area of damage, and will be fixed early next week,” he wrote.

A peeling section of blue coating is seen in the Lincoln Memorial reflecting pool. Photo: AAP

The vandalism claims come amid heightened scrutiny of the $20 million, which was done through expedited no-bid contracts to firms with ties to Trump. The connections have fuelled criticism about taxpayer funds were used to reward the President’s political allies.

Trump had said his predecessors had let the pool turn an algae-stained green and that he would line it with “American flag blue” so it better reflected the Washington Monument.

But the new pool took only a few days to switch from bright blue to its familiar green. Then painted blue lining on the bottom began to peel.

The pool renovation is part of Trump’s plans to remake the US capital city. They also include tearing down the East Wing of the White House for a new ballroom and building a massive arch near Arlington ​National Cemetery where the US honours its war dead and other ​prominent Americans.

-with AAP