United Technologies Corp. (IW 1000/59) rose the most in almost seven years after CNBC reported that Honeywell International Inc. (IW 1000/105) approached the company about a possible merger.

The aerospace giants have held talks within the past two weeks about a possible deal in which Honeywell would offer a premium, CNBC said on February 22, citing unidentified people familiar with the situation.

United Technologies is concerned that a merger attempt may not pass a regulatory review, according to the report.

A United Technologies spokesman declined to comment on the report. A Honeywell representative wasn’t immediately available to comment.

United Technologies shares surged 6.8% to $94.20 at 1:55 p.m. in New York after an earlier gain of 7.6%, the largest intraday advance since March 2009.  Honeywell rose 0.8% $108.13.

Talks began last year when United Technologies approached Honeywell about a merger that would put United Technologies management in control of the combined company, CNBC said. After a decline in United Technologies’ stock price led to a breakdown in talks, Honeywell countered with an offer structured as a merger of equals, the network said.