LONDON (Reuters) - A couple of mammoth mergers drove the value of takeovers of British companies to their highest level since the financial crisis during the first quarter, official data showed on Tuesday.

The Office for National Statistics said the value of takeovers of British companies rose to 49.4 billion pounds ($72.0 billion)in the first three months of the year, the highest amount since the second quarter of 2007 and up from 9.2 billion pounds at the end of 2015.

Almost all of this reflected the $52 billion merger of Royal Dutch Shell and BG Group.

The value of takeovers between British companies rose to 11.6 billion pounds, up from 1.2 billion pounds in the fourth quarter and the highest since the end of 2008.

The ONS said this mostly reflected BT Group's purchase of mobile operator EE.

The number of both foreign and domestic takeovers fell during the first quarter compared with the last three months of 2015, the ONS said.

(Reporting by Andy Bruce, editing by David Milliken)