WASHINGTON - U.S. President Donald Trump on Tuesday applauded two National Football League teams that largely steered clear of controversy by standing for the national anthem at Monday night's game, even as players protested in other ways.

At the match-up in Phoenix, the Dallas Cowboys linked arms and knelt on the playing field, then stood for the playing of the "Star-Spangled Banner." Arizona Cardinals players also joined arms but did not kneel.

"But while Dallas dropped to its knees as a team, they all stood up for our National Anthem. Big progress being made-we all love our country!" Trump wrote in a series of early-morning posts on Twitter, continuing his war of words with the multibillion dollar NFL.

"Ratings for NFL football are way down except before game starts, when people tune in to see whether or not our country will be disrespected!" he added.

It was the latest salvo from Trump, a former reality television show host and political neophyte who took office in January, after he ignited the fight with the players in the biggest-grossing U.S. pro sports league last week.

On Friday, he told a political rally that any protesting player was a "son of a bitch" who should be fired, and urged a boycott of NFL games, touching off protests by dozens of players, coaches and some owners before games on Sunday.

Kneeling during the anthem began last year when former San Francisco 49ers quarterback Colin Kaepernick refused to stand to protest police shootings of African-Americans.

Several players have made similar gestures, saying their actions are a call for social justice and protected by the American right to free speech, not a slight against the country or its flag. Critics, including Trump, have said it is disrespectful.

Trump's verbal assault may play well with his conservative base at a time when the Republican president is grappling with North Korea's nuclear threats, a humanitarian crisis in hurricane-struck Puerto Rico, an investigation of Russian meddling in the 2016 election and a healthcare struggle in Congress.

The weekend controversy so far appeared to have a mixed impact on televised games. CBS Corp CBS.N said overall viewership of its broadcasts were higher on Sunday while NBC, owned by Comcast Corp CMCSA.O , said viewership was down. Fox, owned by Twenty-First Century Fox Inc FOXA.O , also reported lower viewership, CNN reported. (Reporting by Susan Heavey; Editing by Jeffrey Benkoe) ((202-898-8300; Reuters Messaging: susan.heavey.thomsonreuters.com@reuters.net))