* Dollar falls 1 pct vs yen as investors seek safe haven
* Trump immigration actions prompt risk-off trade
* Mexican peso hits highest level of 2017 vs dollar (Updates to U.S. market open, new throughout)
By Dion Rabouin
NEW YORK, Jan 30 (Reuters) - The dollar fell more than 1 percent against the Japanese yen on Monday following a weekend of negative headlines relating to U.S. President Donald Trump's executive orders on immigration.
Trump's order to temporarily ban the entry of refugees and people from seven Muslim-majority countries faced mounting criticism, even from some prominent Republicans, and sparked protests that drew tens of thousands in major American cities.
"The first week in office was really not focused on fiscal policy or growth or any of the supply-side enhancing measures," said Mark McCormick (NYSE:MKC), North American head of FX strategy at TD Securities in Toronto.
"It was really focused on all the negatives around immigration, trade risks, some of the other negative issues, which the market hasn't really been focused on."
The dollar remained weak against the yen, falling by 1.25 percent to 113.67 yen JPY= , as investors sought the traditional security of the Japanese currency as the immigration curbs put the spotlight back on Trump's protectionist bent and the risks it poses for the economy. dollar is being sold a bit because of the reaction to Trump's executive order on immigration, just thinking it could create all sorts of problems with trade partners," said Joseph Trevisani, chief market strategist at Worldwide Markets in Woodcliff Lake, New Jersey. "It's really an emotional reaction to that."
The euro fell to its lowest level since Jan. 19 against the greenback after the release of German inflation data that came in slightly weaker than expected, but retraced much of the move after investors unpacked the data, which showed German consumer price inflation hit the highest in three-and-a-half years. euro was last flat against the dollar at $1.0690.
Sterling GBP= fell 0.25 percent, helping keep the dollar index from significant losses. The index .DXY tracks the greenback against the euro, pound, yen and three other major world currencies. It was last down 0.1 percent at 100.440.
A stronger dollar was one of 2017's big calls for many investment banks and asset managers at the end of last year, but that view has been undermined by worries about how U.S. trade and diplomacy will pan out under Trump's presidency.
The dollar also had been weakened by weaker-than-expected U.S. economic growth data on Friday.
The Mexican MXN= peso rose to its highest level of 2017 on Monday. It gained 3.24 percent last week, its largest weekly percentage gain since February 2016.