US Secretary of State Mike Pompeo has denied Washington was “covering up” the killing of Saudi journalist Jamal Khashoggi and promised further action.

“America is not covering up for a murder,” Mr Pompeo told reporters in Budapest when asked about criticism by a senior Democrat.

The remarks came after US President Donald Trump missed a deadline set by Congress to reply by Friday on whether Saudi Arabia’s powerful Crown Prince Mohammed bin Salman ordered the killing of the Washington Post contributor.

Mr Pompeo said that Mr Trump’s administration was “working diligently” on its investigation.

“The president has been very clear — couldn’t be more clear — as we get additional information, we will continue to hold all of those responsible accountable,” he said.

Mr Khashoggi, who lived in the United States, was strangled to death and dismembered in October after entering the Saudi consulate in Istanbul to take care of paperwork for his marriage, according to officials.

Mr Trump said nothing on the congressional deadline, while congressional aides said that Mr Pompeo had sent them a letter in which he outlined actions over the killing.

The administration revoked the visas of nearly two dozen Saudi officials and froze the assets of 17 others.

But Mr Trump has openly said that he does not care if Prince Mohammed was responsible for the killing as Saudi Arabia buys weapons from the United States and shares his hard line on Iran.

It comes as Mr Mike Pompeo is in Hungary on the first leg of a five-nation European tour during which he will raise concerns about China and Russia’s growing influence in Central Europe.

Mr Pompeo was meeting in Budapest on Monday with Hungary’s nationalist Prime Minister Viktor Orban and other senior officials to stress the importance of promoting democracy and the rule of law.

The US sees those as key to countering Russian and Chinese efforts to pull Hungary and other countries in the region away from the West and sow division in the European Union and NATO, officials said.

Mr Pompeo will specifically point to Central Europe’s reliance on Russian energy and the presence of the Chinese hi-tech telecom firm Huawei, particularly in Hungary, according to the officials, who were not authorised to publicly discuss Mr Pompeo’s travel and spoke on the condition of anonymity.

US officials are deeply troubled by Huawei’s expansion in Europe, especially in NATO member states where they believe it poses significant information security threats.

Mr Pompeo will take the same message to his next stop, Slovakia, on Tuesday, before heading to Poland, where he will participate in a conference on the future of the Middle East expected to focus on Iran.

He will wrap up the tour with brief stops in Belgium and Iceland.

Ahead of his visits to Budapest and Bratislava, US officials said Mr Pompeo hoped to reverse what they called a decade of US disengagement in Central Europe that created a vacuum that Russia and China have exploited.

Over the course of the past 10 years, the officials said, Russian President Vladimir Putin and Chinese leaders have become much more aggressive in the region and made inroads.

One official said Mr Pompeo’s aim is to “wrong-foot the West’s rivals in places where they have gained bridgeheads.”