Top Democrat says Trump seems 'incapable' of being President and does not know what country needs

A US Congressman has questioned Donald Trump's "capability" to continue serving as President.

Democratic Representative Adam Schiff said on CNN that he thinks there is "an issue" with Mr Trump's behaviour.

"There's some attribute of his character that seemingly makes him incapable of introspection and a broad understanding of what the country really needs."

Mr Schiff has been leading the House Intelligence Committee's investigation into alleged ties between Mr Trump's campaign team and Russian officials in parallel to FBI, Senate, and special prosecutor investigations.

Mr Schiff said people are asking questions about the motivation behind the President's actions.

His comments come on the heels of Republican Senator Bob Corker's comments that Mr Trump has not shown the "stability, nor some of the competence" to function as an effective leader of the free world and Commander-in-chief of the US military.

Jackie Speier, Mr Schiff's California colleague in the House of Representatives, said in a tweet that the President is "showing signs of erratic behaviour and mental instability that place the country in grave danger".

She called for invoking the 25th Amendment of the US Constitution, which allows "the Vice President and a majority of either the principal officers of the executive departments" to deem a President as unfit to fulfil the duties of the office, transferring power to the Vice President.

The amendment, drafted after the assassination of President John F Kennedy in 1963, was drawn up to limit power to publicly elected officials should the President die, be under anaesthesia, or be otherwise incapacitated.

It was invoked when Richard Nixon resigned and Gerald Ford became President and later when George W Bush underwent medical procedures requiring anaesthesia. This happened twice during his two terms in office, temporarily making Dick Cheney Acting President.

However, Mr Schiff noted that the situation has not progressed to the point of invoking the 25th Amendment just yet.

"I think what the authors of that amendment principally had in mind was some kind of physical incapacitation or serious mental illness or a breakdown...and I think we're still far from concluding that that's the case, even though we find, many of us, his comment anathema and there to be a serious problem here".