Minister for Finance Michael Noonan kicked off his US visit with a meeting with Treasury Secretary Jack Lew on Monday, during which the European Union's Apple tax ruling reared its ugly head again. 

The US government's chief financial officer reiterated his concerns over what the order for Apple to repay €13bn in back taxes – now being challenged by both the tech giant and Ireland – would mean for trade relations between the EU and the US in the future.

In a statement, the US Treasury revealed that Lew criticised how the EU Commission was retroactively applying "a sweeping new state aid theory that is contrary to well-established legal principles, calls into question the tax rules of individual countries and threatens to undermine the overall business climate in Europe." 

Lew also told Noonan that they shared "the goal of addressing corporate tax avoidance" and highlighted the "meaningful progress" made between the EU and US.

The economic implications of Brexit were also on the agenda, with Lew assuring Noonan that the US was "committed" to working with the EU and UK to "ensure sustained economic stability and shared, global prosperity."

On the subject of Donald Trump winning the US presidential election, Lew said his department was "committed to a smooth transition" to the next administration and "working to ensure the success of the President-elect in leading and uniting the country." Former Goldman Sachs partner Steven Mnuchin is to to be the frontrunner to become Trump's Treasury Secretary.

Noonan also met with the International Monetary Fund (IMF) and the World Bank as part of his US trip yesterday.

He is now set to meet a number of big US multinationals that are based in Ireland. He has no public speaking engagements or interviews planned for the trip, which was arranged before Trump's victory but is now serving as something of a charm offensive following concerns that plans to cut US business tax to 15% could impact our competitiveness when it comes to foreign direct investment.