Top Democrat demands answers on whether Kushner, others used private email for diplomacy Kushner has used three email accounts for White House business.

 -- Amid recent revelations that some White House advisers have used private email accounts to conduct official government business, the top Democrat on the Senate Foreign Relations Committee is demanding to know if any White House officials communicated via private email or text with a representative of a foreign government, political party or international organization.

Sen. Ben Cardin, D-Md., has sent a letter, obtained exclusively by ABC News, to Secretary of State Rex Tillerson and White House counsel Don McGahn asking for that information as well as communications that senior State Department or embassy officials — including Tillerson — had through such “unofficial channels.”

In particular, Cardin is looking at Jared Kushner, a White House adviser and President Trump’s son-in-law, who has played a large role in the administration’s foreign policy.

“Mr. Kushner’s active role in arranging meetings and engaging in diplomacy, both in public and private, coupled with his use of unofficial email, raises questions as to whether any communications regarding representatives of foreign governments occurred through unofficial channels and could have been compromised,” Cardin wrote in the letter.

Kushner has used three email accounts for White House business, sources confirmed for ABC News on Monday.

His portfolio has included Middle East peace negotiations and planning Trump’s trip to Saudi Arabia.

He met twice with Russian officials during the transition and suggested using a back channel at the Russian Embassy to facilitate direct communication between the incoming Trump administration and the Russian government, according to a statement he made before the Senate Intelligence Committee in July.

The committee is investigating Russia’s interference in the 2016 presidential election and any ties between the Trump campaign and Russia.

“It is important that any communications that may have occurred over private email or via other non-governmental platforms are appropriately preserved and secure,” Cardin wrote.

To that end, Cardin wants information on which officials have used private email, as well as copies of those exchanges, by Oct. 17.

A White House spokesperson responded to ABC News’ request for comment, writing, "The White House instructs staff to fully comply with the Presidential Records Act and applicable guidelines for work-related communications. In light of recent congressional inquiries, we have briefed staff on the need to preserve records and working to ensure compliance."

State Department spokesperson Heather Nauert confirmed during a press briefing Tuesday that the department had received the letter, but declined to add anything further.