"Ridiculous!" he exclaimed on Twitter.
"Their intimidation and abuse of American citizens is shameful". Caputo did not attend the meeting and, according to his lawyer, has no documents about it.
The State Department pledged to "work cooperatively with the committees".
The probe comes following mid-term elections in the USA that gave Democrats a majority over Trump's Republicans in the House.
The House Democrats demanded documents and information from more than 80 individuals, businesses and institutions on Monday in search of evidence of impeachable offenses.
Asked by reporters whether he would cooperate with the probe, Trump said, "I cooperate all the time with everybody".
But Giuliani said: "I can not discuss conversations with other counsel other than to say anyone who asked me about pardons I repeated what president has said that pardons would not be considered at this time". "No collusion. It's all a hoax".
The committee's investigation will cast a wider net than Mueller, whose investigation is focused on specific crimes.
The White House has lashed out at congressional Democrats, calling a sweeping request by a House of Representative committee for files from dozens of President Donald Trump associates "disgraceful and abusive".
The requests also target the Republican decision in July 2016 to moderate the official party stance against Russian interference in Ukraine, and seek information on Trump campaign contacts with WikiLeaks and any sharing of data, like polling data, between the campaign and Russia. The happy news is that such an effort necessarily implicates American voters, who will be placed in a position to judge Team Trump for themselves through public hearings-rather than from the cold words on the page of a hypothetical special counsel report.
Among the committee's aims is determining whether Trump may have obstructed justice by ousting perceived enemies at the Justice Department, such as former FBI Director James Comey, and abused his presidential power by possibly offering pardons or tampering with witnesses.
Eric Trump, one of the president's sons who helps lead the Trump Organisation, also spoke out about a document request he received from Nadler.
Nadler said in most of the letters that he was limiting the requests to documents that had already been provided to other investigators, an attempt to receive as much as possible in the two-week timeline.
"We may add other people".
The President pushed harder for his son-in-law to get a clearance because of his wide-ranging portfolio, which includes a Middle East peace proposal, and because of heightened scrutiny on Kushner's inability to secure a clearance, sources said.
The last big investigation involving a US president - the Ken Starr probe into the Whitewater scandal and former President Bill Clinton's relationship with Monica Lewinsky - differed in that it was carried out by an independent counsel, which unlike a special counsel is not part of the Justice Department.