TOKYO (Reuters) -S&P Global Ratings said on Friday it has downgraded its rating of Nissan Motor's ( NSANF ) credit by one notch on continuing pressure on its profitability, while taking a negative view of the outlook for the Japanese automaker.

The credit-rating firm cut its long-term rating on the company and its overseas subsidiaries to "BB-" from "BB". It noted that the company's competitiveness in key markets and operational efficiency have diminished.

"Tariff costs, a challenging competitive landscape, and rising expenses under inflationary pressures serve as headwinds to its performance recovery," S&P said in a statement.