Nicola Sturgeon and Boris Johnson urged the public to pull together and help each other through tough new push to beat lethal Covid-19.
The First Minister and Prime Minister made separate televised address - with the same emotional appeal - as all four nations of the UK prepare new restrictions on ordinary life, expected to last six months.
Sturgeon thanked Scots for months of effort to hammer down infections, but warned "the challenged is once again getting harder".
In a short statement, she said: "I know that all of this has been incredibly tough – and six months on it only gets tougher. But never forget that humanity has come through even bigger challenges than this one. And though it doesn’t feel like it now, this virus will pass. It won’t last forever and one day, hopefully soon, we will be looking back on it, not living through it."
The new rules in Scotland place a 10pm curfew on pubs, cafes and restaurants from Friday night.
A nationwide ban has been imposed to stop people visiting other households indoors, extending restrictions already in place across much of west central Scotland.
Similar restrictions are coming into force in England, where the Prime Minister has tightened rules on social gatherings.
Sturgeon said the numbers of cases trebled in the past three weeks, the virus is spreading and people are "sadly dying".
In the past 24 hours, one person has died in Scotland after testing positive for coronavirus. An alarming 383 people tested positive for Covid-19. The Scottish Government confirmed 73 people are currently in hospital with the virus, while 10 are in intensive care.
She added: "So though we are all struggling with this – and believe me, we are all struggling – let’s pull together.
"Let's keep going, try to keep smiling, keep hoping and keep looking out for each other. Be strong, be kind and let’s continue to act out of love and solidarity.
"I will never find the words to thank all of you enough for the enormous sacrifices you have made so far. And I am sorry to be asking for more.
"But a belief I hold on to – and one I am asking you to keep faith with in those moments when it all feels too hard – is this. If we stick with it – and, above all, if we stick together – we will get through it."
In his TV address, Johnson went for the Conservative spirit of Churchillian unity in an attempt to pull the UK together.
As he appealed to the public to obey the "simple rules:" for survival, he said: "Never in our history has our collective destiny and our collective health depended so completely on our individual behaviour."
The Prime Minister added: "If we follow these simple rules together, we will get through this winter together. There are unquestionably difficult months to come. And the fight against covid is by no means over. I have no doubt, however, that there are great days ahead. But now is the time for us all to summon the discipline, and the resolve, and the spirit of togetherness that will carry us through."
But Johnson also warned that "if people don't follow the rules we have set out, then we must reserve the right to go further", signalling that England could follow Scotland in banning household to household meetings.
Large parts of England are already under the same restrictions that have been introduced in the Glasgow area and will now be imposed across Scotland.
Johnson admitted it went against his libertarian values to introduce restrictions on peoples' lives but he was forced to by the prospect of the virus getting out of control.
He said: "I am deeply, spiritually reluctant to make any of these impositions, or infringe anyone's freedom, but unless we take action the risk is that we will have to go for tougher measures later, when the deaths have already mounted and we have a huge caseload of infection such as we had in the spring."
He added: "If we let this virus get out of control now, it would mean that our NHS had no space – once again – to deal with cancer patients and millions of other non-covid medical needs. And if we were forced into a new national lockdown, that would threaten not just jobs and livelihoods but the loving human contact on which we all depend.
"It would mean renewed loneliness and confinement for the elderly and vulnerable, and ultimately it would threaten once again the education of our children. We must do all we can to avoid going down that road again."