Labour leader Jeremy Corbyn has reaffirmed his refusal to meet Theresa May for Brexit talks unless she is prepared to rule out a no-deal break with the EU.

In a letter to the Prime Minister, Mr Corbyn – the only Westminster leader to reject her offer of a meeting – said the talks were “not genuine” and accused her of trying to “play for time”.

Following the crushing defeat of her Brexit deal in the Commons, he said she had – through her spokesmen – rejected a customs union, which he said was necessary for any new deal to win support in Parliament.

He complained she had also made clear she remained unwilling to consider extending the Article 50 withdrawal process – Britain is due to leave the EU on March 29 – or a second referendum.

“Whatever one thinks of those issues, that reinforces the view these are not genuine talks, but designed to play for time and give the appearance of reaching out, while sticking rigidly to your own emphatically rejected deal,” he wrote.

“As I have set out repeatedly in our exchanges across the despatch box and in my previous letter, Labour would support a deal based on a new customs union with a UK say on future trade deals, a strong single market relationship, and guarantees on workers’ rights, consumer standards and environmental protections.

“But meaningful dialogue or negotiations require acknowledgement that your Government’s deal has been decisively rejected, and the Government must now be open to other options that can win support in Parliament.

“And the starting point must be a commitment to rule out ‘no-deal’.”