WASHINGTON – The up-and-down relationship between President Donald Trump and Fox News took another negative turn Friday.

A day after praising a Fox News poll that reflected confidence in his economic record, Trump attacked another Fox News poll that shows him losing the 2020 race to former Democratic Vice President Joe Biden.

"@FoxNews is at it again," Trump said in a tweet. "So different from what they used to be during the 2016 Primaries, & before - Proud Warriors!"

He added another barb: "Now new Fox Polls, which have always been terrible to me (they had me losing BIG to Crooked Hillary), have me down to Sleepy Joe."

Just a day before, Trump touted Fox News data on the economy – "Fox Poll say best Economy in DECADES!" – while ignoring less impressive numbers (a 51% disapproval rating).

Trump continues to give interviews to Fox News hosts – he spoke Thursday with Sean Hannity on his show – but has periodically attacked his favored network on other fronts.

Earlier this month, Trump hit Fox News over the hiring of Democratic consultant Donna Brazile as a political commentator.

Back in April, Trump attacked Fox News anchor Bret Baier over sponsoring a town hall featuring Democratic presidential candidate Bernie Sanders.

That one drew a retweet from Baier, who said "thanks for watching Mr. President" and added that "we cover all sides."

Despite his criticism, there are many examples of Trump praising Fox News polls – when they look good for him.

"New Fox Poll: 58% of people say that the FBI broke the law in investigating Donald J. Trump," the president tweeted in May. In November, he praised a Fox News poll claiming he had a record approval rating among African Americans. Early in the 2016 presidential campaign, Trump praised numerous Fox News polls showing him leading Republican candidates nationally, inIowa and in New Hampshire. He also boasted about a 2015 Fox News poll showing him ahead of then-Democratic candidate Hillary Clinton.

As for the latest survey, the one showing him losing to Biden, Fox anchor Julie Banderas tweeted that Trump "is incorrect" when he suggests that the information is coming from Fox News itself.

"FOX News Opinion Polls are the public’s opinion," she tweeted.

Contributing: John Fritze