A Downing Street spokesperson said:
The Prime Minister held a bilateral meeting with Portuguese Prime Minister António Costa at Downing Street earlier today.
The Prime Minister said that the UK deeply values our long-standing alliance with Portugal and wanted to maintain and strengthen those ties in future across a range of areas, including science, defence, and trade and investment.
They discussed the recent attacks in Syria and Salisbury and agreed that the international community needed to come together to uphold the worldwide prohibition on the use of chemical weapons.
They also discussed Brexit and the progress of negotiations. The Prime Minister underlined the value she placed on the contribution of the Portuguese community in the UK. Prime Minister Costa also welcomed the contribution of UK nationals in Portugal and expressed his desire to maintain a close relationship with the UK after exit.
The Prime Minister also noted that yesterday marked the centenary of the First World War battle of La Lys where the Portuguese suffered their greatest loss of life, and she paid tribute to the bravery of the Portuguese forces.