London's top share index hit record highs, moving above 7,000 points for the first time in its history.
The blue-chip FTSE 100 index rose 0.86% to finish on 7,023 points, led by Irish cement firm CRH, which surged on expectations of lucrative European asset purchases.
The index has been boosted by a positive reaction to this week's UK Budget and fresh hopes of a deal with Greece over its debt re-negotiations.
Retail investors often use the fact that a stock market has risen above such key levels as a sign that a bull market has momentum.
Germany's Dax also set a new record, ending at 12,039 points, the first time the index has closed about 12,000.
European stock markets have been buoyed by a bond-buying programme from the ECB - known as quantitative easing (QE) - that is aimed at boosting growth in the European economy.
Record low interest rates from major world central banks have also pushed down returns on bonds and cash, driving investors to the better returns from shares.
"With a backdrop of easing monetary policy continuing in the US and with the ECB embarking on a €1 trillion QE programme, it was inevitable the FTSE would get past the 7,000 mark," said Dafydd Davies, a partner at Charles Hanover Investments.
CRH advanced 5.9%, adding 3.3 points to the FTSE and making it the best-performing FTSE stock in percentage terms,after Holcim and Lafarge salvaged a planned multi-billion-euro merger to create the world's biggest cement company.
In Dublin, CRH shares were up almost 10%.
CRH has agreed to buy €6.5 billion worth of their assets, which would give competition clearance for the Holcim-Lafarge deal. The new assets would transform CRH into the world's third-biggest building materials supplier.
"The huge sums you speak of could be seen as a negative for the stock, but in this instance and especially given the positive outcome of the Lafarge-Holcim situation, the acquisitions will indeed strengthen CRH's position," Accendo Markets' analyst Augustin Eden said.
British bank TSB - which is not in the main FTSE 100 index - also rose 2.1% after agreeing to a £1.7 billion takeover by Spanish lender Banco Sabadell in one of the biggest cross-border banking deals since the financial crisis of 2007-09.
Lloyds, ordered to sell TSB by regulators as a condition of its £20 billion bailout during the financial crisis, said it had agreed to sell a 9.99% stake to Sabadell and had also undertaken to sell its remaining 40.01%.