President Donald Trump on Saturday threatened to impose a 30% tariff on imports from Mexico and the European Union starting on August 1, after weeks of negotiations with the key U.S. allies and top trading partners failed to reach a comprehensive trade deal.

The European Commission responded to Trump's announcement in a written statement, saying it remains ready to reach an agreement, while also taking "necessary steps to safeguard EU interests, including the adoption of proportionate countermeasures.

The European Union braced on Friday for a possible letter from U.S. President Donald Trump outlining planned duties on the United States' largest trade and investment partner after a broadening of his tariff war in recent days.

The EU remains hopeful it will strike a deal to avoid steep levies Trump has threatened on its exports to the US.

NEW YORK (Reuters) -Investors awaited tariff news between the U.S. and European Union on Friday that could add a potentially volatile development to the end of a week in which President Donald Trump reignited his global trade war.