The phrase "a spokesman has warned" is correct and usable in written English.
It can be used when reporting a caution or alert issued by a representative of an organization or group.
Example: "In a recent press conference, a spokesman has warned that the new policy could lead to significant job losses."
Alternatives: "a representative has cautioned" or "an official has alerted".
China's seizure of a Japanese cargo ship over a pre-war debt could hit business ties, Japan's top government spokesman has warned.
Dr Vincent Cable, the Liberal Democrat Treasury spokesman, has warned of "chaos" for some schools and universities should the company declare itself bankrupt.
Lamb, who is now the party's health spokesman, has warned the NHS is facing collapse within the next few weeks and proposed allowing local areas to raise taxes for extra funds.
I also use mine to access the internet and read news.Eric Latzky, the Philharmonic's spokesman, had warned us that communication in North Korea would be slower and more old-fashioned than usual.
Abbas and other Palestinian spokesmen had warned that they could not negotiate unless it was renewed.
Taliban spokesmen have warned that they are planning large-scale attacks for the day of elections.
Football's economic model is broken and many clubs are in danger of following banks and construction companies into oblivion, the Liberal Democrat Treasury spokesman, Vince Cable, has warned.
Meanwhile, a United Nations spokesman in Gaza has warned that a "health disaster of widespread proportions is rapidly unfolding" there after three weeks of intense conflict.
A spokesman for President Putin, Dmitry Peskov, has warned activists against trying to hold any more pro-Navalny marches without official approval.
Syed Kamall, a spokesman for the Conservative Party in the European Parliament, has warned that the provision could lead to Europe and the United States erecting "a new economic Iron Curtain".
