Donald Trump slammed Hillary Clinton in a series of tweets early Monday as pressure continues over a probe linking the administration to Russia. Trump's administration came under fire after reports surfaced the campaign may have been linked with Russian interference in the 2016 presidential elections.

"Was the brother of John Podesta paid big money to get the sanctions on Russia lifted? Did Hillary know?" Trump wrote in one of the tweets hitting at Clinton. In a follow-up tweet, he asked: "Did Hillary Clinton ever apologise for receiving the answers to the debate? Just asking!"

This is not the first time Trump attacked Clinton over allegations that the Democratic candidate received debate questions in advance of a televised town hall event from Donna Brazile.

"Nobody mentions that Hillary received the questions to the debates," Trump said earlier this year while pushing back against questions about possible ties between his campaign and Russia. "Can you imagine —seriously can you imagine if I received the questions? It would be the electric chair, ok?"

Read: Trump Slams Clinton Uranium Deal On Twitter Amid Rising Tensions On Russia Probe

Last month, Brazile reportedly said that passing along a list of topics to Clinton's campaign was a "mistake I will never forget."

Trump, who is believed to have connections with Russia, has in the past raised questions about why the Clintons are not under investigation for various ties to Russia.

While Trump himself raised concerns about Russian operatives allegedly hacking Democratic Party emails during the election, he and his administration have repeatedly denied any wrongdoing or knowledge of Russia's meddling into the presidential election since well before he was sworn into office. The Federal Bureau of Investigation, as well as the House and Senate Intelligence Committees, are currently examining ties between Trump’s campaign and Russia.

Russian President Vladimir Putin has also denied his country meddled in the November 2016 presidential election between Trump and Clinton.