Trump defends Russian info sharing

US President Donald Trump has defended his decision to share information with Russia, saying he shared facts with Russian officials at an publicly known meeting at the White House last week.

"As President I wanted to share with Russia (at an openly scheduled W.H. meeting) which I have the absolute right to do, facts pertaining ... to terrorism and airline flight safety," he wrote on Twitter.

"Plus I want Russia to greatly step up their fight against ISIS & terrorism," he continued.

Trump met Russian Foreign Minister Sergei Lavrov and Russian Ambassador Sergey Kislyak in the Oval Office last week.

The Washington Post reported on Monday that Trump revealed highly classified information about the Islamic State extremist group during the meeting.

White House officials denied the allegations and called the story "false."

The Russian Foreign Ministry on Tuesday denied the reports, calling them "yet another fake" by the US media.

Russian Foreign Ministry spokeswoman Maria Zakharova wrote in a Facebook post: "Guys, are you reading American newspapers again? You shouldn't. You could use them for something else," Zakharova said.