US lawmakers called on Thursday for Washington to hold Saudi Arabia accountable for the killing of journalist Jamal Khashoggi at one of the country’s consulates in Turkey and vowed that Congress would act if the Trump administration did not.

More than a dozen senators and members of the House of Representatives, including both Democrats and Republicans, spoke at an event in the US Capitol complex to celebrate a free press and remember Khashoggi and more than 50 other journalists killed around the world last year.

Democrats deplored the lack of a strong response to Khashoggi's death from President Donald Trump's administration, saying strategic or commercial ties to Saudi Arabia should not triumph over democratic values like free expression.

“If we decide commercial interests override the statements we make and the actions we take, then we must admit we have lost all moral authority,” House of Representatives Speaker Nancy Pelosi said.

US lawmakers have been clamoring for a response to Khashoggi's murder.

In December, several of Trump's Republicans joined Democrats to defy the president and pass Senate resolutions to end US military support for the Saudi-led coalition in the war in Yemen and blame Crown Prince Mohammed bin Salman for Khashoggi's murder.

The resolutions were not taken up by the Republicans who then led the House, but Democrats plan to revisit the issue after winning a House majority in November's elections.

Representative Mike McCaul, the top House Foreign Affairs Committee Republican, called Khashoggi’s killing “a major setback” in relations. “Changes need to be made,” he said.

Democratic Representative Eliot Engel, the committee’s chairman, told Reuters after the event that he planned hearings on relations with Saudi Arabia in the coming weeks.

Khashoggi, a US-based Washington Post journalist who became a critic of the crown prince, was last seen entering the Saudi consulate in Istanbul on October 2 last year.

US intelligence believes bin Salman ordered an operation to kill Khashoggi. Top Turkish officials have also tied his death to the highest levels of Saudi leadership. Saudi officials have denied accusations that the prince ordered the murder.

Trump, who has cultivated a close relationship with the crown prince, told Reuters last month he stood by the prince despite the CIA assessment.

Secretary of State Mike Pompeo is on a trip to the Middle East, including to Riyadh. A State Department official said he planned to emphasize the need for accountability and credibility in investigating Khashoggi’s death.