Democratic Senator Ron Wyden said Tuesday he will force a vote on repealing the sweeping global tariffs Donald Trump announced last week, testing political support for the president’s trade war.

The Democrat’s gambit will require his Republican colleagues to take a public stand on a tariff offensive that has roiled financial markets for days and raised fears of a recession. GOP senators are showing signs of unease as they are torn between loyalty to the president and anxiety over potential economic damage.

It wasn’t immediately clear how soon the Senate would vote on Wyden’s resolution, which he indicated had some Republican support. He announced he would introduce the measure during a Senate Finance Committee hearing with US Trade Representative Jamieson Greer.

“Today, I am proposing a new bipartisan privileged resolution to end the latest global tariffs that are clobbering American families and small businesses,” Wyden said. The Senate is required to vote on privileged resolutions.

A similar measure to end Trump’s Canada tariffs passed in the Senate after four Republicans joined all Democrats to vote for it. That resolution faces a procedural hurdle in the House and could be vetoed by the president. But such a public break with the president sends a powerful political signal.

Wyden’s resolution would also likely face a presidential veto and opposition from House Republican leaders.

The Democrat’s resolution follows several others aimed at reining in the president’s tariff power. Among them is a bipartisan bill co-sponsored by GOP Senator Chuck Grassley of Iowa and six other Republicans, which would require Congress to review and approve most tariffs within 60 days. The White House said the president would veto Grassley’s measure if it passes.