US president Donald Trump has pledged to send at least 1,000 extra troops to Poland to deter Russian aggression.

He also praised Poland's nationalist-populist government, while again attacking Germany on defence spending and on its Russia gas pipeline.

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Trump has also courted friendly relations with Russian president Vladimir Putin despite Russian aggression in Europe and meddling in US elections (Photo: kremlin.ru)

Trump signed the military deal with Polish president Andrzej Duda in Washington on Wednesday (12 June).

The accord stipulated that Poland would pay for "basing and infrastructure for 1,000 American troops".

But Trump said at a press conference that "they [Poland] are talking about 2,000 troops".

"He [Duda] would like to see 250,000 troops," Trump also joked.

The extra soldiers would complement the 4,500 US soldiers already in Poland on a rotational basis as part of Nato's Russia-deterrent forces sent there after Russia invaded Ukraine.

For his part, Duda said: "Russia again is showing its unkind, unfriendly, imperial face ... Russia is always looking to take our territory".

But Trump, who has courted friendly ties with Russian president Vladimir Putin, played down the Russian threat, while recalling Germany's Second World War assault on Poland.

"I think that Russia will treat Poland with respect ... when bad things happen, it seems that Poland is always the first one that's in there. And it's unfortunate. No, I hope that Russia and Poland and Germany and everybody is going to get along," Trump said.

Poland has called for the extra US troops to be stationed permanently at a new base called "Fort Trump".

The idea has raised heckles from the Kremlin, which claims that it would violate a 1997 Nato-Russia accord.

But Trump noted that the Fort Trump plan had not yet been agreed.

"We haven't totally made up a decision. No. We haven't finalised anything," he said.

"I don't talk about permanence or non-permanence", he added.

Nato head Jens Stoltenberg also praised the idea of more US troops in Poland in remarks from Brussels.

It "shows the strong commitment of the United States to European security and the strength of the transatlantic bond", he noted.

Duda and Orban

Duda's US visit came after Trump recently hosted Hungarian prime minister Viktor Orban at the White House in similar pomp.

Poland and Hungary are under EU sanctions procedures due to attacks on rule of law and backsliding on democracy.

But Trump indicated that Poland had done nothing to merit the EU action.

"They don't want to backslide. They won't backslide ... We're very, very happy with Poland," Trump said.

"Someone cheated you [the US media]. There is no problem with democracy in Poland. Really," Duda also told press.

"Everything is excellent," Duda added. "That's what I hear. OK?," Trump added.

His warm words fell short of allowing Poles to visit America without a visa, even though Poland pledged to buy dozens of US fighter jets and large amounts of liquid natural gas in sweeteners ahead of Wednesday's event.

Germany

The US leader also repeated his previous attacks on Germany for underspending on defence and for building a new gas pipeline with Russia called Nord Stream 2.

He indicated the extra US troops would be moved from Germany to Poland as a punishment for its low contribution to Nato.

"It would be no additional troops to Europe. We'd be moving them from another location ... as you know, we have 52,000 troops in Germany, and Germany is not living up to what they're supposed to be doing with respect to Nato, and Poland is," Trump said.

The number of US troops in Germany is 33,000, according to the US defence department.

Trump declined to say if he would impose sanctions on Anglo-Dutch, Austrian, French, and German firms which are funding Nord Stream 2.

"It's ... something that I've been looking at and I'm thinking about," he said.

Nord Stream 2

The US, as well as eastern and nordic EU countries, see the pipeline as a threat because it would help Russia to cut off energy supplies to Poland and to EU and Nato-aspirant Ukraine.

It would also help to enrich Russia in a move that went against Nato's strategic concerns, Trump noted.

"So, we're protecting Germany from Russia. And Russia is getting billions and billions of dollars of money from Germany," he said.

"I think the German people aren't very happy about it. Because it really makes Germany a hostage of Russia if things ever happened that were bad. Hopefully, that will never be," he added.