Keir Starmer has claimed efforts to cut costs, reduce net migration and boost growth show his “plan is working”. In a rallying cry as Andy Burnham seeks a return to parliament and Wes Streeting vowed to challenge the PM, Mr Starmer highlighted measures to ease the cost-of-living squeeze on families and vowed his Government will “keep pushing forward”. It comes in the face of nearly 100 Labour MPs calling for the PM to stand down in the wake of brutal election results earlier this month across English councils, Wales and Scotland . Mr Starmer, who has insisted he will not walk away from No 10 if the Greater Manchester Mayor wins the June 18 by-election and triggers a leadership contest, has sought to highlight his own record of delivery. He said: “We now have the fastest-growing economy in the G7, net migration has fallen and NHS waiting lists are at their lowest level in three-and-a-half years. Our plan is working. And as summer begins, we are going further to bring down the cost of living and make life easier for families, so they have more room to enjoy it. This Government will keep pushing forward to deliver the change the country voted for.” Office for National Statistics figures showed the economy grew by a higher-than-expected 0.6% over the first quarter, between January and March. Figures this week also showed UK net migration dropped to an estimated 171,000 last year, the lowest level since the start of the coronavirus pandemic. The most recent NHS England data shows the waiting list stood at 7.11 million treatments in March, a fall of 110,073 treatments from February. It comes as Rachel Reeve slashed ticket prices for fairs, theme parks and zoos this summer to ease the cost of living burden on families. The Chancellor said VAT on summer attractions will be cut from 20% to 5% alongside children's meals in restaurants as part of a "Great British Summer Savings" scheme. Estimated to cost around £300million, it will also include free bus travel for children between the ages of five and 15.