President Donald Trump has returned to the campaign trail less than two weeks after testing positive for coronavirus.

He told thousands of supporters, many not wearing masks, that he could give them "a big fat kiss", at a rally in the battleground state of Florida.

His rival, Joe Biden, speaking in Ohio, accused the president of "reckless behaviour" since his diagnosis.

The two presidential candidates are scrambling to secure votes with three weeks until the 3 November election.

Opinion polls suggests Mr Biden has a 10-point lead over Mr Trump nationally. However his lead in some key states is narrower - as is the case in Florida, where the Democrat is 3.7 points ahead, according to an average of polls collated by Real Clear Politics.

Battlegrounds like Florida and Ohio are crucial for gathering the 270 electoral college votes needed to win the White House, which is not determined by a simple popular ballot count.

Mr Trump, 74, tested positive for Covid-19 some 11 days ago, and was admitted to hospital a day later.

But on Sunday his personal doctor said he was no longer a Covid transmission risk to others and disclosed on Monday that his most recent tests were negative over consecutive days, although he did not give the dates.

Trump faithful come out to see their man

At the scene - Nomia Iqbal, BBC News, Sanford, Florida

The usual chants of "Four more years!" were heard as hundreds queued to enter the open air space where the president made his appearance.

People have been getting their temperature checked and were offered face masks. Those who covered up didn't think it was too soon for the president to be out and about. They said they admired him for it. One man here told me he was originally from New York and had made Florida his home - just like "his hero" Donald Trump.

The Trump campaign team is throwing everything at Florida - a loss here makes his return to the White House near impossible.

Vice-President Mike Pence recently visited "The Villages" a famous retirement home to turn out the elderly vote.

But though the president and some of his supporters here seem relaxed about coronavirus, it has hit Florida hard, with more than 15,000 deaths.

Joe Biden, who arrives in the state on Tuesday, is focusing on the administration's handling of the pandemic and plan to carry out a quieter but vigorous campaign in key suburban areas which they hope will help flip the state blue.

What did Trump say at the rally?

In his first stump appearance following his Covid-19 diagnosis and recovery, a re-invigorated Mr Trump returned to his campaign's familiar themes and lines of attack against Mr Biden.

He touted stock market growth, the establishment of the US Space Force and his successful confirmation of two conservative Supreme Court justices to the bench - with a third nominee, Judge Amy Coney Barrett, before the Senate this week - as major achievements.

Before a crowd of several thousand he denounced plans to prolong Covid-related shutdowns supported by Democrats and sought to question Mr Biden's mental acuity.

Referring to his own recovery from Covid-19, he said at one point: "They say I'm immune - I feel so powerful. I'll walk in there and kiss everyone. I'll kiss the guys and the beautiful women, I'll give you a big, fat kiss."

Though reinfections of the virus remain rare scientists are still questioning how much immunity can be built up to the virus.

Few people in the crowd were seen wearing masks or adhering to public health guidelines to keep at least 6ft (2m) apart to reduce the risk of transmitting Covid-19.
Why is Florida so important?

It was no surprise that Florida is the place where Mr Trump made his big rally return.

He wants and needs to win Florida, a state he narrowly carried in 2016. It is also his adopted home. A lifelong New Yorker, he made himself a Florida resident last year in September.

However, President Trump's support from seniors, which helped him win four years ago, appears to be dwindling, with his campaign trying to make up for the losses by courting African American and Hispanic voters.

"Every campaign changes from election to re-election," his campaign manager Bill Stepien told reporters on Monday.

Close races in crucial states like Florida mean Mr Trump may yet win re-election by capturing key electoral college-rich territories.

It is among the six states with the largest number of electoral college votes - 29 of the total of 538 up for grabs.

Mr Trump is stopping in a further three battleground states this week - Pennsylvania (with 20 electoral college votes), Iowa (6) and North Carolina (15).

What about Joe Biden?

The Democrat is set to appear in Florida on Tuesday.

Mr Biden, who made two appearances in the key state of Ohio on Monday, attacked the president's campaigning approach, saying that he "comes to Sanford bringing nothing but reckless behaviour, divisive rhetoric and fear mongering".

President Trump won Ohio by eight percentage points four years ago, however recent polls show this year's race to be tightening. Ohio has 18 electoral college votes.

Mr Biden told car workers who had gathered in American-made vehicles in Toledo: "215,000 dead because of Covid... Trump knew how dangerous the disease was but did nothing. Why didn't he warn us?"

Mr Biden touted his own record in the state, saying he and former President Barack Obama had played a key role in keeping the car industry afloat during the financial crisis and recession 10 years ago.

The 77-year-old has taken a more cautious approach to campaigning, with his team announcing on Monday that he had tested negative for the virus again.

Election officials in a number of key states are already seeing high levels of in-person early voting, with reports of hours-long queues in Georgia on Monday. The US Elections Project, a study run by Florida University professor Michael McDonald, puts the figure of early voters across the US as high as 10.5 million.

A record number of people are also expected to vote by post due to the pandemic.