In a statement, Informa confirmed it had "received an approach" about a merger from UBM and said it was considering the proposal.

However it added "there can be no certainty that any transaction will take place," and gave no timeframe on a further announcement.

UBM also confirmed early talks were underway on the "commercial merits of an all-share merger". Merrill Lynch International is acting for the company.

Informa publishes journals and books for academic, scientific and professional groups. It has more than 150 offices in upwards of 40 countries, staffed by 7,500 people.

UBM's 5,000 staff in more than 30 countries focuses on professional and commercial sectors. Last year, it made more than £800m in revenue with an operating profit of £176m.

Joining forces would see the emergence of a supergroup valued at around £3bn, reports have claimed. Informa is worth around £1.6bn and UBM about £1.5bn.

Informa stands for Innovative, Non-bureaucratic, For profit, Open, Rewarding, Market-focused, About quality.