Ukrainian President Volodymyr Zelensky will arrive in the UK today, in his first visit since Russia’s invasion of Ukraine last year.
Downing Street said he would meet Prime Minister Rishi Sunak and make a speech in Parliament later.
No 10 has also announced that British training of Ukrainian forces will be expanded to cover fighter jet pilots and marines.
It’s also expected the UK will announce fresh sanctions targeting Russia later.
Plans have been announced to train Ukrainian pilots to fly Nato-standard fighter jets in the future, a key request from Ukraine.
President Zelensky addressed MPs in March last year, speaking virtually from Kyiv, the first time a foreign leader addressed MPs in the Commons chamber.
Western countries have been considering how to bolster support for Ukraine, with the country braced for a renewed Russian offensive later this month.
The UK has already announced plans to send Challenger 2 tanks to Ukraine, with Ukrainian troops receiving training in how to operate them.
No 10 said Mr Sunak would be offering to provide Ukraine with “longer range capabilities” to disrupt Russia’s ability to target Ukraine’s critical national infrastructure.
It added that British training would be scaled up this year, with a further 20,000 Ukrainian soldiers set to be trained.