Crime in the District of Columbia has risen almost 10 per cent in the past three months compared to the same period a year ago, a police spokesman said yesterday.

The spokesman said the rise, which began in February and continued through April, is the sharpest in recent years. He said police officials regard the increase as "disturbing" and believe that it "could affect the quality of life downtown" if it protends a trend lasting a year or more.

The figures were released a day after Chief Maurice J. Cullinane testified before Sen. Patrick J. Leahy (D-Vt.) against proposed budget cuts that would reduce the force by 103 officers. The department's present strength is about 4,300 officers, the spokesman said.

The spokesman said department officials believe the force cannot be cut further without reflecting an increase in the city's crime rate. He noted that the department reached a peak strength of 5,100 officers in 1971 and has since undergone cuts by attrition due to a hiring freeze imposed on all city agencies in 1975 by Mayor Walter E. Washington.

In his testimony before Sen. Leahy Wednesday, Chief Cullinane did not discuss crime statistics.

The police spokesman said yesterday the final figure comparing the first three month of 1977 with the same period in 1976 showed a rise of only 6 per cent.

He said that the quarterly statistic was misleading because it conceals a rise of 12.5 per cent in February over figures for the same month a year earlier, and a 7.1 per cent rise in March, 1977, compared to March, 1976. He said these increases were offset in the quarterly report by a 15 per cent drop in crime in January - largely attributed to cold weather - compared to the samemonth a year earlier.