Joe Biden has clarified his assertion that he'll defy any subpoena to testify in Donald Trump's impeachment trial in the US Senate, saying he has always complied with lawful orders.
A day earlier, the Democrat Presidential contender told The Des Moines Register he stood by his position he would defy the Republican-controlled Senate if it ordered him to be a witness in the proceedings.
"Correct," he said when asked if that was still his intent. "And the reason I wouldn't (testify) is because it's all designed to deal with Trump doing what he's done his whole life - trying to take the focus off of him."
In a tweet on Saturday, Biden said: "I want to clarify something I said yesterday. In my 40 years in public life, I have always complied with a lawful order and in my eight years as VP, my office - unlike Donald Trump and Mike Pence - cooperated with legitimate congressional oversight requests."

Democratic presidential candidate and former vice president Joe Biden. Source: Getty Images North America
Yet he followed with another tweet suggesting that he would consider any subpoena from the Senate Republicans for the impeachment trial to be illegitimate.
"I am just not going to pretend that there is any legal basis for Republican subpoenas for my testimony in the impeachment trial," he tweeted. "That is the point I was making yesterday and I reiterate: this impeachment is about Trump's conduct, not mine."
Trump and some of his allies have threatened to seek testimony from Biden, his son Hunter, and the anonymous whistleblower whose complaint about Trump's July phone call with Ukraine's leader set off the impeachment inquiry.

US President Donald Trump (L) and former US vice president Joe Biden (R), Source: AFP
On the call, Trump asked the Ukrainian president to open an investigation into the Bidens while holding up military aid for Ukraine. A Ukrainian gas company had hired Hunter Biden when his father was vice president and the Obama administration's point man on Ukraine. There is no evidence of wrongdoing by either Biden.