PARIS — They have had their differences, but when President Emmanuel Macron of France and President Trump spoke by telephone on Tuesday about the threat of a new chemical weapons attack by Syria, Mr. Macron seized the opportunity and invited Mr. Trump to Paris for Bastille Day.

It was not immediately clear whether Mr. Trump would accept the invitation, which was also extended to his wife, Melania, according to a statement from the Élysée Palace. But the traditional military parade in Paris on this Bastille Day, July 14, will also commemorate the 100th anniversary of America’s entry into World War I to fight alongside the French, British and other Allies.

While relations between French and American leaders have been marked by friendship and friction since then, Mr. Macron and Mr. Trump got off to a rocky start.

During the French presidential election, Mr. Trump did little to conceal his preference for Mr. Macron’s chief opponent, Marine Le Pen of the far-right National Front.