The charity was forced to defend itself after being labeled by Nigel Farage and others as a “taxi service for illegal trafficking gangs”.
He saw a surge of public support after revealing how his volunteers suffered abuse and posted heartbreaking footage of rescues.
The RNLI said it received more than £ 200,000 in donations on Wednesday alone, a 2,000% increase the day before and well above the daily average of £ 6,000-7,000.
It also saw an increase in the number of people looking for information on how to volunteer with the rescue charity.
Jayne George, RNLI Fundraising Director, said: “We are overwhelmed by the tremendous support we have received from our amazing supporters over the past two days.
“We have seen an increase in donations, with over £ 200,000 given yesterday just through a combination of one-time donations, regular new support and supporters increasing their regular donation amounts. It is simply amazing.
She said the charity had also seen a “small number” of previous supporters withdraw their support for operations involving asylum seekers.
Health secretary Saijd Javid was among prominent figures claiming he donated on Wednesday and sharing the association’s website on Twitter so others can do the same.
The RNLI has become a target for right-wing commentators and extremists over the past year, amid record numbers of small boats crossing the Channel.
Jayda Fransen, the former deputy chief of Britain First, has been among those calling on people to stop donating, while anti-migrant groups operating on the south coast have accused them of “escorting people in hiding” and ” support the invasion ”.
Mr Farage, the former head of Ukip, reiterated that the charity was a “taxi service for gangs of illegal traffickers”.
The RNLI said its only goal is to save lives at sea and that it does not distinguish between the different types of incidents where people are in danger.
The charity has no role in the enforcement of immigration laws or border control, and hands responsibility for any rescued person to the appropriate authorities when they reach dry land.
Dominic Raab, the foreign minister, said the RNLI had continued to operate within the law and to do “incredible work”.
He added: “At the same time, if we are talking about the larger issue of small boats, this is something where, absolutely at the same time, we have to strive as much as humanly possible, working with our partners. French. “
Priti Patel pledged to make small boat crossings ‘unsustainable’ last summer, but that pledge was followed by a record number that continued to grow.
Last week the government announced a deal to more than double the number of police patrolling French beaches, with the UK giving France an additional £ 54million.
It follows several similar deals in recent years that have seen little success, and critics have questioned efforts to deter migrants with Facebook ads containing messages such as’ don’t put your life or yours on the line. child in danger ”and“ we will bring you back ”.
The UK has not been able to send asylum seekers to the EU countries they have passed through, including France, since January 1 due to the expiration of a key deal with Brexit.
Several EU countries have declared The independent they would not sign any new commitment to deal with deported asylum seekers and that negotiations are not underway.
The Home Office lobbied to jail asylum seekers who run small boats as “human traffickers,” but prosecution has been limited by new guidelines from the Crown Prosecution Service (CPS).
The Nationality and Borders Bill, if enacted, would criminalize any migrant who reaches the UK on small boats by creating a new offense of knowingly arriving in the UK without a valid entry permit.
It would also make it easier to prosecute people who run boats or assist asylum seekers who arrive on irregular routes.
It is not possible to apply for asylum in the UK from abroad or to apply for an entry permit abroad for the purpose of applying for asylum.
According to figures from the Ministry of the Interior, at least 2,000 migrants are currently massing around the region of Calais in the hope of crossing the Channel.
Overall, UK asylum claims have declined, but small boat crossings have increased dramatically after the coronavirus pandemic led to a decrease in freight and passenger traffic.