A witness who testified before the Hunter Biden grand jury was asked to identify the “big guy” in the first son’s planned deal with a Chinese energy conglomerate — as calls ramped up to have President Biden included in a conspiracy probe.

The question arose after the witness was shown a piece of evidence while appearing in secret before the panel in Wilmington, Del., a source familiar with the proceedings told The Post.

A bombshell email exclusively reported by The Post in October 2020 showed that one of Hunter Biden’s business partners, James Gilliar, outlined the proposed percentage distribution of equity in a company created for a joint venture with CEFC China Energy Co.

The March 13, 2017, plan included “10 held by H for the big guy?”

Another former Hunter Biden partner, US Navy veteran Tony Bobulinski, later revealed that “the big guy” was Hunter’s dad, then the Democratic candidate for president, saying, “I have heard Joe Biden say he has never discussed his dealings with Hunter. That is false.”

Hunter Biden disclosed he was under investigation for his “tax affairs” shortly after his dad was elected over former President Donald Trump in the 2020 election, but the probe broadened to include potential money laundering and the violation of lobbying laws, according to recent reports.

In the wake of last week’s report by the Washington Post — which confirmed $4.8 million in payments from CEFC to entities controlled by Hunter Biden and first brother James Biden during 2017 and 2018 — the White House on Sunday attempted to distance the president from his under-scrutiny kin....