New Delhi: Prime Minister Narendra Modi today greeted BJP veteran Lal Krishna Advani on his 90th birthday and said his efforts have contributed richly to the building of the party. In a series of tweets, he said the former deputy prime minister has distinguished himself through hard work and dedication towards the nation. He said Advani is a political stalwart, a leader who has distinguished himself through hard work and dedication towards the nation. "We BJP karyakartas (workers) are fortunate to always receive the guidance of Advani ji. His efforts have contributed richly to the building of BJP," he said.