The New York Times Co laid off 100 employees on Thursday and cut salaries for the rest of the year by 5 percent, and said it might cut newsroom jobs at its namesake newspaper if it cannot get union employees to agree to a similar cut.

The news, which the Times released in two memos from company executives, comes on the same day rival newspaper The Washington Post said it wants to buy out an unspecified number of employees.

Both papers are suffering from a decline in advertising revenue. The Times's parent company is dealing with a heavy debt load and running an expensive news operation. The Washington Post is operating in the red.

The Times said nonunion employees at the New York Times Media Group, The Boston Globe and other units will take a 5 percent pay cut. At other units, including its Worcester newspaper and other papers, the cut would be 2.5 percent.

About 100 employees at The New York Times's business operation are losing their jobs. About 15 unionized employees were laid off, according to a statement on Thursday from the Newspaper Guild of New York. It is unclear whether those 15 are included in the 100 cuts.

This was a very difficult decision to make, said one of the memos, which was signed by New York Times Co Chairman Arthur Sulzberger Jr and Times Co Chief Executive Janet Robinson. The environment we are in is the toughest we have seen in our years in business.

The Times urged unionized employees to agree to the pay cut, as well as an increased amount of vacation time. A letter signed by several executives, including top New York Times Editor Bill Keller said union participation in New York could help avoid the possibility of newsroom layoffs.

New York Times shares were up 23 cents, or 5.03 percent, at $4.80 on the New York Stock Exchange in afternoon trading.

(Editing by Andre Grenon)