Donald Trump, Jr. criticized former Vice President Joe Biden on Wednesday for refusing to take questions from reporters after calling for the president’s impeachment.

Trump, Jr., who is quickly becoming one of the GOP’s top campaign surrogates, took to social media to lambast Biden for avoiding the media at a press conference convened to announce his position on impeachment. The business executive suggested Biden was freezing out the media so he would not have to address the mounting questions about his son’s business dealings China and Ukraine.

“Because not a lot of sons of politicians get $50,000 a month from foreigners to consult on energy policy with no prior energy experience,” Trump, Jr. wrote, adding: “Also investors (China) don’t give people with 0 investment experience $1,500,000,000… unless you’re buying them!”

Because not a lot of son’s of politicians get $50,000 a month from foreigners to consult on energy policy with no prior energy experience. Also investors (China) don’t give people with 0 investment experience $1,500,000,000… unless you’re buying them! https://t.co/15RGGNaBI4 — Donald Trump Jr. (@DonaldJTrumpJr) September 24, 2019

Since announcing his presidential campaign, the former vice president has refused to discuss the ties his youngest son, Hunter, has cultivated overseas. Biden has remained silent on the topic, even though there is increasing evidence such dealings were made easier because of his political influence. As Peter Schweizer, a contributing editor at Breitbart News, detailed in his book— Secret Empires: How the American Political Class Hides Corruption and Enriches Family and Friends — Hunter Biden profited off extraordinary deals that were unavailable to regular citizens.

In Ukraine, alone, the younger Biden secured a lucrative appointment to the board of directors of the country’s only independent oil and natural gas company, Burisma Holdings, in 2014. Hunter Biden received the position, which reportedly paid as much $83,000-a-month, despite no prior background in Ukraine or the energy industry. Around the same time as the appointment, Joe Biden was tapped as the Obama administration’s point man on Ukraine in the wake of Russia’s annexation of Crimea.

Hunter Biden’s appointment and the subsequent pressure Joe Biden placed on the Ukrainian government to fire the prosecutor investigating the company for corruption is at the center of the push for impeachment. Democrats claim that President Donald Trump allegedly broke the law by suggesting to the newly elected-president of Ukraine, Volodymr Zelensky, that he probe Hunter Biden’s ties to Burisma.

The president has defended his conduct publicly, pointing out the inconsistencies and contradictions both Joe and Hunter Biden have told on the topic.

“The conversation I had was largely … [about] all of the corruption taking place and largely the fact that we don’t want our people like Vice President Biden and his son creating the corruption already in the Ukraine and Ukraine has got a lot of problems,” the president said on Saturday.