Donald Trump launched a preemptive strike against a possible independent conservative candidate Sunday after it was announced that an 'impressive' candidate with a 'real chance' was just on the horizon.

Bill Kristol, editor of The Weekly Standard and known to be one of a group of anti-Trump pundits looking to block Trump's ascension, made the announcement at 10pm Sunday.

Two hours later Trump took to Twitter, calling Kristol a 'dummy' and promising that a 'spoiler' candidate would hand the Presidency - and the Supreme Court - to the Democrats, Fox News reported.

Promise: Bill Kristol (pictured), editor of The Weekly Standard, promised an 'impressive' independent conservative candidate with a 'real chance' of taking on presumptive Republican candidate Donald Trump

Spoiler: Trump responded to Kristol's Tweet by calling Kristol a 'dummy' and a 'lightweight' and saying a 'spoiler' candidate would give the presidency and Supreme Court to the Democratic Party candidate

'Impressive': Kristol has not yet named his 'impressive' candidate, whom he announced Sunday, but has been noted talking to Mitt Romney, who had also been looking for an anti-Trump candidate earlier this month

'Lightweights': Trump fought back with characteristic vigor. Kristol and a number of other conservatives distrust Trump and doubt his conservative credentials

'Spoiler': Trump warned against splitting the conservative voter base, saying it would only help the Democrats

'The Republican Party has to be smart & strong if it wants to win in November,' Trump wrote. 'Can't allow lightweights to set up a spoiler Indie candidate!'

He added: 'If dummy Bill Kristol actually does get a spoiler to run as an Independent, say good bye to the Supreme Court!'

Those messages were prompted by Kristol's own Tweet, which read: 'Just a heads up over this holiday weekend: There will be an independent candidate - an impressive one, with a strong team and a real chance.'

On Monday he added: 'I'm traveling, so hadn't realized I'd so upset @realDonaldTrump. I'm sorry the mere mention of an independent candidate has so unnerved him.

'I hope my mention of an independent candidate didn't distract him while paying respects during whichever Memorial Day ceremony he attended.'

Kristol is one of a number of Republicans who doubt that Trump is committed to conservative values, and seek to offer what they see as a more reliable alternative.

That's no small matter - finding someone who wants to throw themselves in the path of Trump, a man who already bested 16 contenders and is now the presumptive nominee, as well as the money needed is quite a task.

And getting a new name on the ballot this late into the run for president is a challenge too.

But Kristol seems to think he's got a viable candidate - and the Trump team are taking that threat seriously.

Speaking to Fox News on Monday, Ben Carson - one of the candidates bested by Trump, and now firmly on his team, likened to situation to the 1992 presidential election, which saw George H.W. Bush losing out to Bill Clinton.

'A quarter of a century ago, another Clinton was running for the White House,' Carson said, 'and it was the entrance of a third-party candidate - Ross Perot - that made it possible for him to win.

'Wouldn’t it be ironic if the same thing happened this time?'

Defender: Ben Carson appeared on Fox News to back up Trump, saying that Ross Perot's independent run in 1992 handed the presidency to Bill Clinton and that history could repeat itself in 2016

Kristol's potential independent president has yet to be named, but he has previously been noted talking to Mitt Romney, another notable anti-Trump figure who has been casting about for a potential contender.

And on Monday he linked to an article by Carrie Sheffield on conservative Buzzfeed-a-like Bold that unfavorably compared one of Trump's Memorial Day Tweets with one by Romney.

'I would like to wish everyone, including all haters and losers (of which, sadly, there are many) a truly happy and enjoyable Memorial Day!' Trump wrote.

Meanwhile, Romney quoted Ronald Regan, saying 'Today is the day we put aside to remember fallen heroes and to pray that no heroes will ever have to die for us again.'

The article criticizes concludes: 'no wonder then that so many voters are fed up with the designated Republican and Democratic candidates and are very open to a third-party alternative.'

Kristol called it a 'must read'.

'Upset': On Monday Kristol mockingly apologized for 'upsetting' Donald Trump. He also Tweeted an article by another journalist that said Trump's Memorial Day Tweets were disrespectful compared to Romneys