Paul Ryan turns on Donald Trump as Republicans move to block planned tariffs

Not everyone in the US Republican Party thinks the harsh tariffs are a good idea. Photo/File.

Congressional Republicans are manoeuvring to stop US president Donald Trump from levying harsh tariffs on steel and aluminium imports, arguing the move runs counter to the core of their economic agenda and could even cause political problems heading into the 2018 midterms.

"We are extremely worried about the consequences of a trade war and are urging the White House to not advance with this plan," AshLee Strong, a spokeswoman for House Speaker Paul Ryan said in a statement yesterday. "The new tax reform law has boosted the economy and we certainly don't want to jeopardise those gains."

Members of the House Ways and Means Committee were also circulating a letter arguing against the tariffs, and high-ranking Senate Republicans have voiced their opposition.

It's unclear whether the GOP pushback will have any effect on Trump, who surprised fellow Republicans Thursday when he announced tariffs of 25 per cent on steel imports and 10 per cent on aluminium imports. He has since dug in deeper on the plans, defending them in a string of posts on Twitter.

We are on the losing side of almost all trade deals. Our friends and enemies have taken advantage of the U.S. for many years. Our Steel and Aluminum industries are dead. Sorry, it’s time for a change! MAKE AMERICA GREAT AGAIN!

— Donald J. Trump (@realDonaldTrump) March 5, 2018

To protect our Country we must protect American Steel! #AMERICA FIRST

— Donald J. Trump (@realDonaldTrump) March 5, 2018

For all of the controversies Trump has faced, the tariffs decision is one of few times he's taken a step that runs directly counter to Republicans' legislative and economic goals. Many Republicans have voiced concerns the move will undermine the US$1.5 trillion tax cut bill they passed in December.

They also said it could cause political problems ahead of 2018 midterms. Democrats hope to take back control of the House and Senate in November, while Republicans planned to run on an economic argument to defend their majorities.

But it's difficult to predict how far Republicans would go to stand up to Trump.

The tariff decision has not yet been finalised, but that's expected to happen in the next week or two. The goal of congressional Republicans is to keep that from happening; but if that fails, other options remain on the table, according to a congressional aide who spoke anonymously to discuss the private deliberations.

The Constitution gives Congress the authority over taxation and tariffs, but Congress has delegated trade negotiation and tariff authority to the president over recent decades. Congressional leaders believe that approach has worked well - until now.

A spokeswoman for House Ways and Means Committee Chairman Kevin Brady, said in a statement that "the administration and Congress must work together on trade policies that build off the momentum of the President's tax cuts, which is why any tariffs should be narrow, targeted, and focused on addressing unfairly traded products, without disrupting the flow of fairly traded products for American businesses and consumers."