Definition: In this task, you need to generate an appropriate title for the given summary of some paragraph. The generated title must be short and should include the main topic of the given text. Your summary should be less than 20 words long.
Input: Irish Prime Minister Leo Varadkar has said he will tell Theresa May that it is "an absolute red line" that there is no hard Irish border after Brexit.

Theresa May and Leo Varadkar meet in Sofia