Doctors have cleared Republican Senate leader Mitch McConnell to work after he suddenly became unable to speak for the second time this summer.

Brian Monahan, the attending physician of the US Congress, said he had consulted with Mr McConnell and his neurology team about the matter.

After being asked if he would run for re-election, McConnell, 81, froze for over 30 seconds.

He had a similar lapse in July.

In Covington, Kentucky, the senator was unable to answer questions, which were repeated by staff members.

Before leaving with aides, McConnell made no comment about his health. The aides later said he was feeling lightheaded.

He suffered from a concussion after falling at an event in March, according to staff.

Dr Monahan said in a statement on Thursday: “Occasional lightheadedness is not uncommon in concussion recovery and can also be expected as a result of dehydration.”

Politico reported that a handful of Republican senators were weighing whether Mr McConnell should stay on as leader.

According to Marjorie Taylor Greene, a Republican congresswoman, McConnell is not “fit for office.”

“Our nation’s leaders must address severe aging health issues and/or mental health incompetence,” said Ms Greene, also mentioning the age of US President Joe Biden, who is 80.

In a social media post, Democratic congressman Dean Phillips called for term limits for members of Congress and the Supreme Court.

In a statement on Thursday, Vice President Joe Biden said he recently spoke with Mr McConnell and that he seemed to be doing well.

In Washington DC, Mr Biden told reporters: “He’s a friend, and I talked to him today, and he was as good as ever.

Mr Biden said he had no concerns about McConnell’s fitness for office.